Wednesday, April 8, 2015

StaticCodeInstructionConstraintException

com.sun.org.apache.bcel.internal.verifier.exc.StaticCodeInstructionConstraintException

StaticCodeInstructionConstraintException is described in the javadoc comments as:

Instances of this class are thrown by BCEL's class file verifier 'JustIce' when a class file to verify does not pass the verification pass 3 because of a violation of a static constraint as described in the Java Virtual Machine Specification, Second edition, 4.8.1, pages 133-137. The static constraints checking part of pass 3 is called pass 3a in JustIce. Static constraints on the instructions in the code array are checked early in pass 3a and are described on page 134 in the Java Virtual Machine Specification, Second Edition.
version: $Id: StaticCodeInstructionConstraintException.java,v 1.1.1.1 2001/10/29 20:00:33 jvanzyl Exp $ author: Enver Haase

Where is this exception thrown?

Following, is a list of exception messages cross-referenced to the source code responsible for throwing them. Click on the method link to view the code and see how the exception is thrown.

How is this exception thrown?

The following sub-sections identify where this exception is thrown, and how (or why) the code is throwing the exception.

Any source code quoted in this section is subject to the Java Research License unless stated otherwise.

com.sun.org.apache.bcel.internal.verifier.statics.Pass3aVerifier.pass3StaticInstructionChecks()

/**
  * These are the checks if constraints are satisfied which are described in the
  * Java Virtual Machine Specification, Second Edition as Static Constraints on
  * the instructions of Java Virtual Machine Code (chapter 4.8.1).
  *
  * @throws StaticCodeConstraintException if the verification fails.
  */
private void pass3StaticInstructionChecks() {
    if (!(code.getCode().length < 65536)) {
        throw new StaticCodeInstructionConstraintException('Code array in code attribute '' + code + '' too big: must be smaller than 65536 bytes.');
    }
    InstructionHandle ih = instructionList.getStart();
    while (ih != null) {
        Instruction i = ih.getInstruction();
        if (i instanceof IMPDEP1) {
            throw new StaticCodeInstructionConstraintException('IMPDEP1 must not be in the code, it is an illegal instruction for _internal_ JVM use!');
        }
        if (i instanceof IMPDEP2) {
            throw new StaticCodeInstructionConstraintException('IMPDEP2 must not be in the code, it is an illegal instruction for _internal_ JVM use!');
        }
        if (i instanceof BREAKPOINT) {
            throw new StaticCodeInstructionConstraintException('BREAKPOINT must not be in the code, it is an illegal instruction for _internal_ JVM use!');
        }
        ih = ih.getNext();
    }
    Instruction last = instructionList.getEnd().getInstruction();
    if (!((last instanceof ReturnInstruction) || (last instanceof RET) || (last instanceof GotoInstruction) || (last instanceof ATHROW))) throw new StaticCodeInstructionConstraintException('Execution must not fall off the bottom of the code array. This constraint is enforced statically as some existing verifiers do - so it may be a false alarm if the last instruction is not reachable.');
}

Source: "Java SE Downloads: Java SE 6 JDK Source Code", at: http://www.oracle.com/technetwork/java/javase/downloads/index.html

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