1081 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			HTML
		
	
	
	
			
		
		
	
	
			1081 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			HTML
		
	
	
	
| <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
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| 
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| <html>
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|   <head>
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|     <title>Java bytecode constraints</title>
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|     <link rel=stylesheet href="java-constraints.css">
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|   </head>
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| 
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|   <body>
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|     <h1>
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|       Bytecode constraints
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|     </h1>
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| 
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|     <p>
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|       From the point of view of a piece of code written in the Java
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|       programming language or targeted in the same way to <code>.class</code>
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|       files, the Dalvik VM aims to behave in a way
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|       that is fully consistent with the language's definition.
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|       That is, the code running in Dalvik will behave the same as it
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|       would have running in any other virtual machine. This includes
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|       verification failures.
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|       The Dx/Dalvik system will check roughly the same
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|       constraints that any other VM would, except as noted in the file
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|       <a href="verifier.html">verifier.html</a>. The following table briefly
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|       lists all Dx/Dalvik verification constraints together their analogs
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|       from the book <i>The Java<super>TM</super> Language Specification</i>,
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|       second edition. In the numbering scheme, the first three
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|       elements refer to the specification chapter, the fourth one to the
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|       bullet inside that chapter. The failure mode specifies whether the
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|       constraint will fail during the Dx conversion or during verification in
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|       the VM itself.
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|     </p>
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| 
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|     <h2>
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|       Static constraints
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|     </h2>
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| 
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|     <p>
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|     Static constraints are constraints on individual elements of the bytecode.
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|     They usually can be checked without employing control or data-flow analysis
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|     techniques.
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|     </p>
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| 
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|     <table>
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|       <tr>
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|         <th>
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|           Identifier
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|         </th>
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| 
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|         <th>
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|           Description
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|         </th>
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| 
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|         <th>
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|           Spec equivalent
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|         </th>
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| 
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|         <th>
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|           Failure mode
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|         </th>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A1
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|         </td>
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| 
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|         <td>
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|           The <code>code</code> array must not be empty.
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|         </td>
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| 
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|         <td>
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|           4.8.1.1
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A2
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|         </td>
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| 
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|         <td>
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|           The <code>code</code> array must not be larger than 65535 bytes.
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|         </td>
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| 
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|         <td>
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|           4.8.1.2
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A3
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|         </td>
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| 
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|         <td>
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|           The first opcode in <code>code</code> array must have index
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|           <code>0</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.3
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A4
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|         </td>
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| 
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|         <td>
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|           The <code>code</code> array must only contain valid opcodes.
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|         </td>
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| 
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|         <td>
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|           4.8.1.4
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A5
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|         </td>
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| 
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|         <td>
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|           The index of instruction <code>n+1</code> must equal the index of
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|           instruction <code>n</code> plus the length of instruction
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|           <code>n</code>, taking into account a possible <code>wide</code>
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|           instruction. Opcodes modified by a <code>wide</code> instruction must
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|           not be directly reachable.
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|         </td>
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| 
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|         <td>
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|           4.8.1.5
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A6
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|         </td>
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| 
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|         <td>
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|           The last instruction in <code>code</code> array must end at index
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|           <code>code_length-1</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.6
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A7
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|         </td>
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| 
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|         <td>
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|           All jump and branch targets must be opcodes within the same method.
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|           Opcodes modified by a <code>wide</code> instruction must not be
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|           directly reachable via a jump or branch instruction.
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|         </td>
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| 
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|         <td>
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|           4.8.1.7
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A8
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|         </td>
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| 
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|         <td>
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|           All targets of a <code>tableswitch</code> instruction must be opcodes
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|           within the same method. Upper and lower bounds must be consistent.
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|           Opcodes modified by a <code>wide</code> instruction must not be
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|           directly reachable via a <code>tableswitch</code> instruction.
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|         </td>
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| 
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|         <td>
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|           4.8.1.8
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A9
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|         </td>
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| 
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|         <td>
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|           All targets of a <code>lookupswitch</code> instruction must be opcodes
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|           within the same method. Its table must be consistent and sorted
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|           low-to-high. Opcodes modified by a <code>wide</code> instruction must
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|           not be directly reachable via a <code>lookupswitch</code> instruction.
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|         </td>
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| 
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|         <td>
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|           4.8.1.9
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A10
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|         </td>
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| 
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|         <td>
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|           The operands of <code>ldc</code> and <code>ldc_w</code> instructions
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|           must be valid indices into the constant pool. The respective entries
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|           must be of type <code>CONSTANT_Integer</code>,
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|           <code>CONSTANT_Float</code>, or <code>CONSTANT_String</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.10
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A11
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|         </td>
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| 
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|         <td>
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|           The operands of <code>ldc2_w</code> instructions must be valid indices
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|           into the constant pool. The respective entries must be of type
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|           <code>CONSTANT_Long</code> or <code>CONSTANT_Double</code>. The
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|           subsequent constant pool entry must be valid and remain unused.
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|         </td>
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| 
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|         <td>
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|           4.8.1.11
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A12
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|         </td>
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| 
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|         <td>
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|           The Operands of <code>get<kind></code> and
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|           <code>put<kind></code> instructions must be valid indices into
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|           constant pool. The respective entries must be of type
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|           <code>CONSTANT_Fieldref</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.12
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A13
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|         </td>
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| 
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|         <td>
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|           The first two operands of <code>invokevirtual</code>,
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|           <code>invokespecial</code>, and <code>invokestatic</code> must form a
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|           valid 16-bit index into the constant pool. The respective entries must
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|           be of type <code>CONSTANT_Methodref</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.13
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A14
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|         </td>
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| 
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|         <td>
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|           Methods whose names start with '<' must only be invoked implicitly by
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|           the VM, not by class file code. The only exception is the instance
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|           initializer, which may be invoked by <code>invokespecial</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.14
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A15
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|         </td>
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| 
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|         <td>
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|           The first two operands of <code>invokeinterface</code> must form a
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|           valid 16-bit index into the constant pool. The entry must be of type
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|           <code>CONSTANT_Interface_Methodref</code>. The third operand must
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|           specify number of local variables and the fourth operand must always
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|           be zero.
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|         </td>
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| 
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|         <td>
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|           4.8.1.15
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A16
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|         </td>
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| 
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|         <td>
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|           The operands of <code>instanceof</code>, <code>checkcast</code>,
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|           <code>new</code>, and <code>anewarray</code> instructions must
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|           be a valid index into the constant pool. The first two operands of
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|           <code>multianewarray</code> instruction must form a valid 16-bit index
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|           into the constant pool. All respective entries must be of type
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|           <code>CONSTANT_Class</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.16
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|      <tr>
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|         <td>
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|           A17
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|         </td>
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| 
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|         <td>
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|           The dimensions of an array created by <code>anewarray</code>
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|           instructions must be less than <code>256</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.17
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A18
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|         </td>
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| 
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|         <td>
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|           The <code>new</code> instruction must not reference array classes,
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|           interfaces, or abstract classes.
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|         </td>
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| 
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|         <td>
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|           4.8.1.18
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A19
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|         </td>
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| 
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|         <td>
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|           The type referenced by a <code>multinewarray</code> instruction must
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|           have at least as many dimensions as specified in the instruction. The
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|           dimensions operand must not be <code>0</code>
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|         </td>
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| 
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|         <td>
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|           4.8.1.19
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A20
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|         </td>
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| 
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|         <td>
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|           The type referenced by a <code>newarray</code> instruction must be a
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|           valid, non-reference type.
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|         </td>
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| 
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|         <td>
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|           4.8.1.20
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A21
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|         </td>
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| 
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|         <td>
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|           The index operand of instructions explicitly referencing single-width
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|           local variables must be non-negative and smaller than
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|           <code>max_locals</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.21
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A22
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|         </td>
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| 
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|         <td>
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|           The index operand of instructions implicitly referencing single-width
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|           local variables must be non-negative and smaller than
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|           <code>max_locals</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.22
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
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|       <tr>
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|         <td>
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|           A23
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|         </td>
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| 
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|         <td>
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|           The index operand of instructions explicitly referencing double-width
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|           local variables must be non-negative and smaller than
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|           <code>max_locals-1</code>.
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|         </td>
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| 
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|         <td>
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|           4.8.1.23
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
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|       </tr>
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| 
 | |
|       <tr>
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|         <td>
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|           A24
 | |
|         </td>
 | |
| 
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|         <td>
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|           The index operand of instructions implicitly referencing double-width
 | |
|           local variables must be non-negative and smaller than
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|           <code>max_locals-1</code>.
 | |
|         </td>
 | |
| 
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|         <td>
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|           4.8.1.24
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|         </td>
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| 
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|         <td>
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|           DX
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|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           A25
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           The index operand of <code>wide</code> instructions explicitly
 | |
|           referencing single-width local variables must be non-negative and
 | |
|           smaller than <code>max_locals</code>.
 | |
|         </td>
 | |
| 
 | |
|         <td>
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|           4.8.1.25
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|         </td>
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| 
 | |
|         <td>
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|           DX
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|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           A26
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           The index operand of <code>wide</code> instructions explicitly
 | |
|           referencing double-width local variables must be non-negative and
 | |
|           smaller than <code>max_locals-1</code>.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.1.25
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
|     </table>
 | |
| 
 | |
|     <h2>
 | |
|       Structural constraints
 | |
|     </h2>
 | |
| 
 | |
|     <p>
 | |
|     Structural constraints are constraints on relationships between several
 | |
|     elements of the bytecode. They usually can't be checked without employing
 | |
|     control or data-flow analysis techniques.
 | |
|     </p>
 | |
| 
 | |
|     <table>
 | |
|       <tr>
 | |
|         <th>
 | |
|           Identifier
 | |
|         </th>
 | |
| 
 | |
|         <th>
 | |
|           Description
 | |
|         </th>
 | |
| 
 | |
|         <th>
 | |
|           Spec equivalent
 | |
|         </th>
 | |
| 
 | |
|         <th>
 | |
|           Failure mode
 | |
|         </th>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B1
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           The number and types of arguments (operands and local variables) must
 | |
|           always match the instruction.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.1
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B2
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           The operand stack must have the same depth for all executions paths
 | |
|           leading to an instruction.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.2
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B3
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           Local variable pairs must never be broken up.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.3
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B4
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           A local variable (or pair) has to be assigned first before it can be
 | |
|           read.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.4
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B5
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           The operand stack must never grow beyond <code>max_stack</code>.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.5
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B6
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           The operand stack must never underflow.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.6
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B7
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           An <code>invokespecial</code> instruction must only invoke an instance
 | |
|           initializer or a method in the current class or one of its
 | |
|           superclasses.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.7
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B8
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           An instance initializer must only be invoked on an uninitialized
 | |
|           instance residing on the operand stack.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.8
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B9
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           Instance methods may only be invoked on and instance fields may only
 | |
|           be accessed on already initialized instances.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.9
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B10
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            The must be no backwards branches with uninitialized instances on the
 | |
|            operand stack or in local variables. There must be no code protected
 | |
|            by an exception handler that contains local variables with
 | |
|            uninitialized instances.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.10
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B11
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            An instance initializer must call another instance initializer (same
 | |
|            class or superclass) before any instance members can be accessed.
 | |
|            Exceptions are non-inherited instance fields, which can be assigned
 | |
|            before calling another initializer, and the <code>Object</code> class
 | |
|            in general.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.11
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B12
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            All actual method arguments must be assignment-compatible with formal
 | |
|            arguments.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.12
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B13
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            For each instance method invocation, the actual instance must be
 | |
|            assignment-compatible with the class or interface specified in the
 | |
|            instruction.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.13
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B14
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            A returns instruction must match its method's return type.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.14
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B15
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            When accessing protected members of a superclass, the actual type of
 | |
|            the instance being accessed must be either the current class or one
 | |
|            of its subclasses.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.15
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|      <tr>
 | |
|         <td>
 | |
|           B16
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            The type of a value stored into a static field must be
 | |
|            assignment-compatible with or convertible to the field's type.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.16
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B17
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            The type of a value stored into a field must be assignment-compatible
 | |
|            with or convertible to the field's type.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.17
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B18
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            The type of every value stored into an array must be
 | |
|            assignment-compatible with the array's component type.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.18
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B19
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            The operand of an <code>athrow</code> instruction must be
 | |
|            assignment-compatible with <code>java.lang.Throwable</code>.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.19
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B20
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            The last reachable instruction of a method must either be a backwards
 | |
|            jump or branch, a return, or an <code>athrow</code> instruction. It
 | |
|            must not be possible to leave the <code>code</code> array at the
 | |
|            bottom.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.20
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B21
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            Local variable values must not be used as return addresses.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.21
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B22
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           There must be a single, uniquely determined return instruction per
 | |
|           subroutine call.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.22
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           VM
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B23
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           Subroutine calls must not be directly or indirectly self-recursive.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.23
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|       <tr>
 | |
|         <td>
 | |
|           B24
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|            <code>ReturnAddress</code> instances must not be reused. If a
 | |
|            subroutine returns to a <code>ReturnAddress</code> further up the
 | |
|            stack than where its original call instruction is located, then all
 | |
|            <code>ReturnAddress</code> instances further down the stack must
 | |
|            never be used.
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           4.8.2.24
 | |
|         </td>
 | |
| 
 | |
|         <td>
 | |
|           DX
 | |
|         </td>
 | |
|       </tr>
 | |
| 
 | |
|     </table>
 | |
|   </body>
 | |
| </html>
 |