Example usage for org.objectweb.asm MethodVisitor visitJumpInsn

List of usage examples for org.objectweb.asm MethodVisitor visitJumpInsn

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Introduction

In this page you can find the example usage for org.objectweb.asm MethodVisitor visitJumpInsn.

Prototype

public void visitJumpInsn(final int opcode, final Label label)

Source Link

Document

Visits a jump instruction.

Usage

From source file:org.jboss.byteman.rule.expression.ComparisonExpression.java

License:Open Source License

public void compile(MethodVisitor mv, CompileContext compileContext) throws CompileException {
    // make sure we are at the right source line
    compileContext.notifySourceLine(line);

    Expression oper0 = getOperand(0);
    Expression oper1 = getOperand(1);

    int removed = 0;

    // evaluate the operands and ensure the reuslt is of the correct type for comparison adds 2
    oper0.compile(mv, compileContext);//from  w w  w  .  j  a  va2s  .co  m
    compileTypeConversion(oper0.getType(), comparisonType, mv, compileContext);
    oper1.compile(mv, compileContext);
    compileTypeConversion(oper1.getType(), comparisonType, mv, compileContext);

    // now do the appropriate type of comparison
    if (comparisonType == type.B || comparisonType == type.S || comparisonType == type.S
            || comparisonType == type.I) {
        Label elsetarget = new Label();
        Label endtarget = new Label();
        // we remove 2 words from the stack and then add 1 back
        removed = 2;
        switch (oper) {
        case LT:
            mv.visitJumpInsn(Opcodes.IF_ICMPGE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case LE:
            mv.visitJumpInsn(Opcodes.IF_ICMPGT, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case GT:
            mv.visitJumpInsn(Opcodes.IF_ICMPLE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case GE:
            mv.visitJumpInsn(Opcodes.IF_ICMPLT, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case EQ:
            mv.visitJumpInsn(Opcodes.IF_ICMPNE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case NE:
            mv.visitJumpInsn(Opcodes.IF_ICMPEQ, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        }
    } else if (comparisonType == type.J || comparisonType == type.F || comparisonType == type.D) {
        if (comparisonType == type.J) {
            mv.visitInsn(Opcodes.LCMP);
            // we remove four words from the stack and add 1 back
            removed = 4;
        } else if (comparisonType == type.F) {
            // we remove two words from the stack and add 1 back
            removed = 2;
            mv.visitInsn(Opcodes.FCMPG);
        } else if (comparisonType == type.D) {
            // we remove four words from the stack and add 1 back
            removed = 4;
            mv.visitInsn(Opcodes.DCMPG);
        }
        Label elsetarget = new Label();
        Label endtarget = new Label();
        switch (oper) {
        case LT:
            mv.visitJumpInsn(Opcodes.IFGE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case LE:
            mv.visitJumpInsn(Opcodes.IFGT, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case GT:
            mv.visitJumpInsn(Opcodes.IFLE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case GE:
            mv.visitJumpInsn(Opcodes.IFLT, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case EQ:
            mv.visitJumpInsn(Opcodes.IFNE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case NE:
            mv.visitJumpInsn(Opcodes.IFEQ, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        }
    } else if (comparable) {
        // we add a further two words setting up the relevant test then remove them
        // and also remove the original two words replacing them with a single word
        removed = 4;
        compileContext.addStackCount(2);
        // we need to deal with null values correctly
        // if op1 == null || op2 == null
        // then
        //   EQ:
        //   push value1 == value2
        //   NE:
        //   push value1 != value2
        //   ow:
        //   push false
        // else
        //   execute compareTo or equals and test for the desired outcome
        // end if
        Label splittarget = new Label(); // else
        Label jointarget = new Label(); // end if
        mv.visitInsn(Opcodes.DUP2); // [... op1, op2 ] ==> [... op1, op2, op1,  op2]
        mv.visitInsn(Opcodes.POP); // [... op1, op2, op1, op2 ] ==> [... op1, op2, op1]
        // if op1 == null
        mv.visitJumpInsn(Opcodes.IFNULL, splittarget); // [... op1, op2, op1] ==> [... op1, op2]
        mv.visitInsn(Opcodes.DUP); // [... op1, op2 ] ==> [... op1, op2, op2]
        // || op2 == null
        mv.visitJumpInsn(Opcodes.IFNULL, splittarget); // [... op1, op2, op2] ==> [... op1, op2]
        // so, it is ok to call compareTo leaving an int or equals leaving a boolean
        if (oper != EQ && oper != NE) {
            mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/lang/Comparable", "compareTo",
                    "(Ljava/lang/Object;)I");
        } else {
            mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Object", "equals", "(Ljava/lang/Object;)Z");
        }
        // now if we did a compareTo we need to generate the required boolean
        Label elsetarget = new Label();
        Label endtarget = new Label();
        // if needed the convert the compareTo result to the required boolean outcome
        switch (oper) {
        case LT:
            mv.visitJumpInsn(Opcodes.IFGE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case LE:
            mv.visitJumpInsn(Opcodes.IFGT, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case GT:
            mv.visitJumpInsn(Opcodes.IFLE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case GE:
            mv.visitJumpInsn(Opcodes.IFLT, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
            break;
        case NE:
            mv.visitJumpInsn(Opcodes.IFEQ, elsetarget);
            mv.visitLdcInsn(false);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(true);
            mv.visitLabel(endtarget);
            break;
        }
        // skip to the join point
        mv.visitJumpInsn(Opcodes.GOTO, jointarget);
        // label the split point
        mv.visitLabel(splittarget);
        if (oper == EQ) {
            elsetarget = new Label();
            endtarget = new Label();
            mv.visitJumpInsn(Opcodes.IF_ACMPEQ, elsetarget);
            mv.visitLdcInsn(false);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(true);
            mv.visitLabel(endtarget);
        } else if (oper == NE) {
            elsetarget = new Label();
            endtarget = new Label();
            mv.visitJumpInsn(Opcodes.IF_ACMPNE, elsetarget);
            mv.visitLdcInsn(false);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(true);
            mv.visitLabel(endtarget);
        } else {
            // pop the operands and stack false
            mv.visitInsn(Opcodes.POP2);
            mv.visitLdcInsn(false);
        }
        // label the join point
        mv.visitLabel(jointarget);
    } else if (comparisonType == Type.Z) {
        // unboxed booleans need special treatment
        // we remove two words replacing them with a single word
        removed = 2;
        Label elsetarget = new Label();
        Label endtarget = new Label();
        mv.visitJumpInsn(Opcodes.IFEQ, elsetarget);
        // on this branch for EQ the stacked value is what we need and for NE
        // the stacked value needs flipping
        if (oper == NE) {
            Label elsetarget2 = new Label();
            mv.visitJumpInsn(Opcodes.IFEQ, elsetarget2);
            mv.visitLdcInsn(false);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget2);
            mv.visitLdcInsn(true);
        }
        mv.visitJumpInsn(Opcodes.GOTO, endtarget);
        mv.visitLabel(elsetarget);
        // on this branch for NE the stacked value is what we need and for EQ
        // the stacked value needs flipping
        if (oper == EQ) {
            Label elsetarget2 = new Label();
            mv.visitJumpInsn(Opcodes.IFEQ, elsetarget2);
            mv.visitLdcInsn(false);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget2);
            mv.visitLdcInsn(true);
        }
        mv.visitLabel(endtarget);

    } else if (comparisonType == Type.BOOLEAN) {
        // boxed booleans need special treatment
        // we remove two words replacing them with a single word
        removed = 2;
        Label elsetarget = new Label();
        Label endtarget = new Label();
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java.lang.Boolean", "equals", "(Ljava/lang/Boolean;)Z");
        if (oper == NE) {
            mv.visitJumpInsn(Opcodes.IFEQ, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
        }
    } else {
        // we remove two words replacing them with a single word
        removed = 2;
        Label elsetarget = new Label();
        Label endtarget = new Label();
        if (oper == EQ) {
            mv.visitJumpInsn(Opcodes.IF_ACMPNE, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
        } else {
            mv.visitJumpInsn(Opcodes.IF_ACMPEQ, elsetarget);
            mv.visitLdcInsn(true);
            mv.visitJumpInsn(Opcodes.GOTO, endtarget);
            mv.visitLabel(elsetarget);
            mv.visitLdcInsn(false);
            mv.visitLabel(endtarget);
        }
    }
    compileContext.addStackCount(1 - removed);
}

From source file:org.jboss.byteman.rule.expression.ConditionalEvalExpression.java

License:Open Source License

public void compile(MethodVisitor mv, CompileContext compileContext) throws CompileException {
    // make sure we are at the right source line
    compileContext.notifySourceLine(line);

    Expression oper0 = getOperand(0);
    Expression oper1 = getOperand(1);
    Expression oper2 = getOperand(2);

    int currentStack = compileContext.getStackCount();
    int expected = (type.getNBytes() > 4 ? 2 : 1);

    // compile the first operand to a boolean and ensure it is primitive -- adds 1 to stack
    oper0.compile(mv, compileContext);//  www  .j av  a 2  s.  c  o  m
    if (oper0.getType() == Type.BOOLEAN) {
        compileBooleanConversion(Type.BOOLEAN, Type.Z, mv, compileContext);
    }
    // plant the test -- consumes 1 word
    Label elseLabel = new Label();
    Label endLabel = new Label();
    mv.visitJumpInsn(Opcodes.IFEQ, elseLabel);
    compileContext.addStackCount(-1);
    // compile the if branch
    oper1.compile(mv, compileContext);
    // make sure we type convert to our result type so that either branch stacks the same thing
    compileTypeConversion(oper1.getType(), type, mv, compileContext);
    // plant a goto skipping over the else expression
    mv.visitJumpInsn(Opcodes.GOTO, endLabel);
    // check the stack height is what we expect, either 1 or 2 words depending upon the result type
    if (compileContext.getStackCount() != currentStack + expected) {
        throw new CompileException("ConditionalEvalExpression.compile : invalid true branch stack height "
                + compileContext.getStackCount() + " expecting " + currentStack + expected);
    }
    // ok, now reset stack height for false branch
    compileContext.addStackCount(-expected);
    // else starts here
    mv.visitLabel(elseLabel);
    // compile the else branch
    oper2.compile(mv, compileContext);
    // make sure we type convert to our result type so that either branch stacks the same thing
    compileTypeConversion(oper2.getType(), type, mv, compileContext);
    // the end is nigh
    mv.visitLabel(endLabel);

    // check the stack height is what we expect, either 1 or 2 words depending upon the result type
    if (compileContext.getStackCount() != currentStack + expected) {
        throw new CompileException("ConditionalEvalExpression.compile : invalid false branch stack height "
                + compileContext.getStackCount() + " expecting " + currentStack + expected);
    }

    // no need to check max stack height as teh left and right expressions will have exceeded anything
    // we stacked inside this call
}

From source file:org.jboss.byteman.rule.expression.LogicalExpression.java

License:Open Source License

public void compile(MethodVisitor mv, CompileContext compileContext) throws CompileException {
    // make sure we are at the right source line
    compileContext.notifySourceLine(line);

    Expression oper0 = getOperand(0);
    Expression oper1 = getOperand(1);

    int currentStack = compileContext.getStackCount();

    // compile the first expression and make sure it is a boolean -- adds 1 to stack height
    oper0.compile(mv, compileContext);/*from w  ww  .ja  va2s  .  c  o  m*/
    if (oper0.getType() == Type.BOOLEAN) {
        compileBooleanConversion(Type.BOOLEAN, type.Z, mv, compileContext);
    }
    // plant a test and branch
    Label nextLabel = new Label();
    Label endLabel = new Label();
    if (oper == AND) {
        // only try next if we got true here
        mv.visitJumpInsn(Opcodes.IFNE, nextLabel);
        // ok, the first branch was false so stack a false for the result and skip to the end
        mv.visitLdcInsn(false);
        mv.visitJumpInsn(Opcodes.GOTO, endLabel);
    } else {
        // only try next if we got false here
        mv.visitJumpInsn(Opcodes.IFEQ, nextLabel);
        // ok, the first branch was true so stack a true for the result and skip to the end
        mv.visitLdcInsn(true);
        mv.visitJumpInsn(Opcodes.GOTO, endLabel);
    }
    // in either case if we get here the if test removed 1 from the stack
    compileContext.addStackCount(-1);
    // the else branch -- adds 1 to stack height
    mv.visitLabel(nextLabel);
    oper1.compile(mv, compileContext);
    if (oper0.getType() == Type.BOOLEAN) {
        compileBooleanConversion(Type.BOOLEAN, type.Z, mv, compileContext);
    }
    // the final result is the result of the second oper which is on the stack already
    // This is the end, my beau-tiful friend
    mv.visitLabel(endLabel);
    // in either case if we get here we should have one extra value on the stack
    // check stack height
    if (compileContext.getStackCount() != currentStack + 1) {
        throw new CompileException("LogicalExpression.compile : invalid stack height "
                + compileContext.getStackCount() + " expecting " + (currentStack + 1));
    }
}

From source file:org.jboss.byteman.rule.expression.StringPlusExpression.java

License:Open Source License

public void compile(MethodVisitor mv, CompileContext compileContext) throws CompileException {
    // make sure we are at the right source line
    compileContext.notifySourceLine(line);

    Expression oper0 = getOperand(0);
    Expression oper1 = getOperand(1);

    int currentStack = compileContext.getStackCount();
    int expected = 1;

    // compile and type convert each operand n.b. the type conversion will ensure that
    // null operands are replaced with "null"

    oper0.compile(mv, compileContext);//from w  ww .jav a2s  .  c  om
    compileTypeConversion(oper0.getType(), type, mv, compileContext);
    oper1.compile(mv, compileContext);
    compileTypeConversion(oper1.getType(), type, mv, compileContext);

    // ok, we could optimize this for the case where the left or right operand is a String plus expression
    // by employing a StringBuffer but for now we will just evaluate the left and right operand and
    // then call concat to join them
    // add two strings leaving one string

    // if second operand is null replace it with "null"
    Label skiptarget = new Label();
    // this adds a word then removes it -- do so to ensure the max height gets updated if need be
    mv.visitInsn(Opcodes.DUP);
    compileContext.addStackCount(1);
    // if it is not null we skip to the concat operation
    mv.visitJumpInsn(Opcodes.IFNONNULL, skiptarget);
    compileContext.addStackCount(-1);
    // it's null so we have to swap it fdr "null"
    mv.visitInsn(Opcodes.POP);
    mv.visitLdcInsn("null");
    mv.visitLabel(skiptarget);
    mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "concat",
            "(Ljava/lang/String;)Ljava/lang/String;");

    compileContext.addStackCount(-1);

    if (compileContext.getStackCount() != currentStack + expected) {
        throw new CompileException("StringPlusExpression.compile : invalid stack height "
                + compileContext.getStackCount() + " expecting " + currentStack + expected);
    }
}

From source file:org.jboss.byteman.rule.RuleElement.java

License:Open Source License

protected void compileStringConversion(Type fromType, Type toType, MethodVisitor mv,
        CompileContext compileContext) throws CompileException {
    assert toType == Type.STRING;
    if (fromType.isObject() || fromType.isArray() || (fromType.isNumeric() && !fromType.isPrimitive())) {
        // use the toString method if the object is non null otherwise just replace it with null
        Label elseLabel = new Label();
        Label endLabel = new Label();
        // if (object == null)
        mv.visitInsn(Opcodes.DUP);/*from ww w  .  j  a v a2 s .c om*/
        // the above dup bumps the stack height
        compileContext.addStackCount(1);
        mv.visitJumpInsn(Opcodes.IFNONNULL, elseLabel);
        compileContext.addStackCount(-1);
        // then string = "null"
        mv.visitInsn(Opcodes.POP);
        mv.visitInsn(Opcodes.ACONST_NULL);
        mv.visitJumpInsn(Opcodes.GOTO, endLabel);
        // else string = object.toString()
        mv.visitLabel(elseLabel);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Object", "toString", "()Ljava/lang/String;");
        mv.visitLabel(endLabel);
    } else if (fromType == Type.Z) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Boolean", "toString", "(Z)Ljava/lang/String;");
    } else if (fromType == Type.B) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Byte", "toString", "(B)Ljava/lang/String;");
    } else if (fromType == Type.S) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Short", "toString", "(S)Ljava/lang/String;");
    } else if (fromType == Type.C) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Character", "toString", "(C)Ljava/lang/String;");
    } else if (fromType == Type.I) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Integer", "toString", "(I)Ljava/lang/String;");
    } else if (fromType == Type.J) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Long", "toString", "(J)Ljava/lang/String;");
        compileContext.addStackCount(-1);
    } else if (fromType == Type.F) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Float", "toString", "(F)Ljava/lang/String;");
    } else if (fromType == Type.D) {
        // use the toString method
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "java/lang/Double", "toString", "(D)Ljava/lang/String;");
        compileContext.addStackCount(-1);
    }
}

From source file:org.kjots.json.object.JsonObjectGeneratorBase.java

License:Apache License

/**
 * Generate a get Java primitive property method.
 *
 * @param classVisitor The class visitor.
 * @param jsonObjectImplType The type of the JSON object implementation.
 * @param method The method./*from  w  w  w.  j ava 2  s .  co m*/
 * @param propertyName The name of the property.
 * @param jsonPrimitiveType The type of the JSON primitive.
 * @param javaPrimitiveType The type of the Java primitive.
 */
private void generateGetJavaPrimitivePropertyMethod(ClassVisitor classVisitor, Type jsonObjectImplType,
        Method method, String propertyName, Type jsonPrimitiveType, Type javaPrimitiveType) {
    MethodVisitor methodVisitor = classVisitor.visitMethod(ACC_PUBLIC + ACC_FINAL, method, null, null);

    Label start = new Label();
    Label l0 = new Label();
    Label l1 = new Label();
    Label end = new Label();

    methodVisitor.visitCode();

    methodVisitor.visitLabel(start);
    methodVisitor.visitVarInsn(ALOAD, 0);
    methodVisitor.visitLdcInsn(propertyName);
    methodVisitor.visitMethodInsn(INVOKEVIRTUAL, jsonObjectImplType,
            this.getGetJsonPrimitivePropertyMethod(jsonPrimitiveType));
    methodVisitor.visitVarInsn(ASTORE, 1);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitJumpInsn(IFNULL, l0);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitMethodInsn(INVOKEVIRTUAL, jsonPrimitiveType,
            this.getToJavaPrimitiveMethod(javaPrimitiveType));
    methodVisitor.visitJumpInsn(GOTO, l1);
    methodVisitor.visitLabel(l0);
    methodVisitor.visitFrame(Opcodes.F_APPEND, 1, new Object[] { jsonPrimitiveType }, 0, null);
    methodVisitor.visitInsn(this.getDefaultConstOpcode(javaPrimitiveType));
    methodVisitor.visitLabel(l1);
    methodVisitor.visitFrame(Opcodes.F_SAME1, 0, null, 1,
            new Object[] { this.getStackElement(javaPrimitiveType) });
    methodVisitor.visitInsn(javaPrimitiveType.getOpcode(IRETURN));
    methodVisitor.visitLabel(end);

    methodVisitor.visitLocalVariable("this", jsonObjectImplType, null, start, end, 0);
    methodVisitor.visitLocalVariable("_" + propertyName, jsonPrimitiveType, null, start, end, 1);
    methodVisitor.visitMaxs(2, 2);

    methodVisitor.visitEnd();
}

From source file:org.kjots.json.object.JsonObjectGeneratorBase.java

License:Apache License

/**
 * Generate a get Java character primitive property method.
 *
 * @param classVisitor The class visitor.
 * @param jsonObjectImplType The type of the JSON object implementation.
 * @param method The method./* w w  w.  j  a  va  2  s  .co m*/
 * @param propertyName The name of the property.
 */
private void generateGetJavaCharacterPrimitivePropertyMethod(ClassVisitor classVisitor, Type jsonObjectImplType,
        Method method, String propertyName) {
    Type jsonStringPrimitiveType = Type.getType(String.class);

    MethodVisitor methodVisitor = classVisitor.visitMethod(ACC_PUBLIC + ACC_FINAL, method, null, null);

    Label start = new Label();
    Label l0 = new Label();
    Label l1 = new Label();
    Label end = new Label();

    methodVisitor.visitCode();

    methodVisitor.visitLabel(start);
    methodVisitor.visitVarInsn(ALOAD, 0);
    methodVisitor.visitLdcInsn(propertyName);
    methodVisitor.visitMethodInsn(INVOKEVIRTUAL, jsonObjectImplType,
            this.getGetJsonPrimitivePropertyMethod(jsonStringPrimitiveType));
    methodVisitor.visitVarInsn(ASTORE, 1);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitJumpInsn(IFNULL, l0);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitMethodInsn(INVOKEVIRTUAL, jsonStringPrimitiveType,
            new Method("isEmpty", Type.BOOLEAN_TYPE, new Type[] {}));
    methodVisitor.visitJumpInsn(IFNE, l0);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitInsn(ICONST_0);
    methodVisitor.visitMethodInsn(INVOKEVIRTUAL, jsonStringPrimitiveType,
            new Method("charAt", Type.CHAR_TYPE, new Type[] { Type.INT_TYPE }));
    methodVisitor.visitJumpInsn(GOTO, l1);
    methodVisitor.visitLabel(l0);
    methodVisitor.visitFrame(Opcodes.F_APPEND, 1, new Object[] { jsonStringPrimitiveType }, 0, null);
    methodVisitor.visitInsn(ICONST_0);
    methodVisitor.visitLabel(l1);
    methodVisitor.visitFrame(Opcodes.F_SAME1, 0, null, 1, new Object[] { Opcodes.INTEGER });
    methodVisitor.visitInsn(IRETURN);
    methodVisitor.visitLabel(end);

    methodVisitor.visitLocalVariable("this", jsonObjectImplType, null, start, end, 0);
    methodVisitor.visitLocalVariable("_" + propertyName, jsonStringPrimitiveType, null, start, end, 1);
    methodVisitor.visitMaxs(2, 2);

    methodVisitor.visitEnd();
}

From source file:org.kjots.json.object.JsonObjectGeneratorBase.java

License:Apache License

/**
 * Generate a get composite JSON object property method.
 *
 * @param classVisitor The class visitor.
 * @param jsonObjectImplType The type of the JSON object implementation.
 * @param method The method.// w w w .  java 2 s .co m
 * @param propertyName The name of the property.
 * @param jsonObjectType The type of the JSON object.
 * @param elementType The type of the element.
 */
private void generateGetCompositeJsonObjectPropertyMethod(ClassVisitor classVisitor, Type jsonObjectImplType,
        Method method, String propertyName, Type jsonObjectType, Type elementType) {
    MethodVisitor methodVisitor = classVisitor.visitMethod(ACC_PUBLIC + ACC_FINAL, method, null, null);

    Label start = new Label();
    Label l0 = new Label();
    Label l1 = new Label();
    Label end = new Label();

    methodVisitor.visitCode();

    methodVisitor.visitLabel(start);
    methodVisitor.visitVarInsn(ALOAD, 0);
    methodVisitor.visitLdcInsn(propertyName);
    methodVisitor.visitLdcInsn(jsonObjectType);
    methodVisitor.visitMethodInsn(INVOKEVIRTUAL, jsonObjectImplType, this.getGetJsonObjectPropertyMethod());
    methodVisitor.visitTypeInsn(CHECKCAST, jsonObjectType);
    methodVisitor.visitVarInsn(ASTORE, 1);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitJumpInsn(IFNULL, l0);
    methodVisitor.visitVarInsn(ALOAD, 1);
    methodVisitor.visitLdcInsn(elementType);
    methodVisitor.visitMethodInsn(INVOKEINTERFACE, jsonObjectType,
            this.getCastCompositeJsonObjectElementMethod(jsonObjectType));
    methodVisitor.visitJumpInsn(GOTO, l1);
    methodVisitor.visitLabel(l0);
    methodVisitor.visitFrame(Opcodes.F_APPEND, 1, new Object[] { jsonObjectType }, 0, null);
    methodVisitor.visitInsn(ACONST_NULL);
    methodVisitor.visitLabel(l1);
    methodVisitor.visitFrame(Opcodes.F_SAME1, 0, null, 1, new Object[] { jsonObjectType });
    methodVisitor.visitInsn(ARETURN);
    methodVisitor.visitLabel(end);

    methodVisitor.visitLocalVariable("this", jsonObjectImplType, null, start, end, 0);
    methodVisitor.visitLocalVariable("_" + propertyName, jsonObjectType, null, start, end, 1);
    methodVisitor.visitMaxs(3, 2);

    methodVisitor.visitEnd();
}

From source file:org.lanternpowered.server.event.ClassEventListenerFactory.java

License:MIT License

private static byte[] generateClass(String name, Class<?> handle, Method method, Class<?> eventClass,
        Class<? extends EventFilter> filter) {
    name = name.replace('.', '/');
    final String handleName = Type.getInternalName(handle);
    final String handleDescriptor = Type.getDescriptor(handle);
    final String filterName = Type.getInternalName(filter);
    String eventDescriptor = "(";
    for (int i = 0; i < method.getParameterCount(); i++) {
        eventDescriptor += Type.getDescriptor(method.getParameterTypes()[i]);
    }//from  w  ww.j  ava 2s . com
    eventDescriptor += ")V";

    ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
    MethodVisitor mv;
    FieldVisitor fv;

    cw.visit(V1_6, ACC_PUBLIC + ACC_FINAL + ACC_SUPER, name, null, BASE_HANDLER, null);
    {
        fv = cw.visitField(ACC_PRIVATE + ACC_STATIC, "FILTER", "L" + filterName + ";", null, null);
        fv.visitEnd();
    }
    {
        mv = cw.visitMethod(ACC_STATIC, "<clinit>", "()V", null, null);
        mv.visitCode();
        mv.visitTypeInsn(NEW, filterName);
        mv.visitInsn(DUP);
        mv.visitMethodInsn(INVOKESPECIAL, filterName, "<init>", "()V", false);
        mv.visitFieldInsn(PUTSTATIC, name, "FILTER", "L" + filterName + ";");
        mv.visitInsn(RETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }
    {
        mv = cw.visitMethod(ACC_PUBLIC, "<init>", '(' + handleDescriptor + ")V", null, null);
        mv.visitCode();
        mv.visitVarInsn(ALOAD, 0);
        mv.visitVarInsn(ALOAD, 1);
        mv.visitMethodInsn(INVOKESPECIAL, BASE_HANDLER, "<init>", "(Ljava/lang/Object;)V", false);
        mv.visitInsn(RETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }
    {
        mv = cw.visitMethod(ACC_PUBLIC, "handle", HANDLE_METHOD_DESCRIPTOR, null,
                new String[] { "java/lang/Exception" });
        mv.visitCode();
        mv.visitFieldInsn(GETSTATIC, name, "FILTER", "L" + filterName + ";");
        mv.visitVarInsn(ALOAD, 1);
        mv.visitMethodInsn(INVOKEINTERFACE, Type.getInternalName(EventFilter.class), "filter",
                FILTER_DESCRIPTOR, true);
        mv.visitVarInsn(ASTORE, 2);
        mv.visitVarInsn(ALOAD, 2);
        Label l2 = new Label();
        mv.visitJumpInsn(IFNULL, l2);
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, name, "handle", "Ljava/lang/Object;");
        mv.visitTypeInsn(CHECKCAST, handleName);
        for (int i = 0; i < method.getParameterCount(); i++) {
            mv.visitVarInsn(ALOAD, 2);
            mv.visitIntInsn(BIPUSH, i);
            mv.visitInsn(AALOAD);
            Type paramType = Type.getType(method.getParameterTypes()[i]);
            GeneratorUtils.visitUnboxingMethod(mv, paramType);
        }
        mv.visitMethodInsn(INVOKEVIRTUAL, handleName, method.getName(), eventDescriptor, false);
        mv.visitLabel(l2);
        mv.visitInsn(RETURN);
        mv.visitMaxs(0, 0);
        mv.visitEnd();
    }
    cw.visitEnd();

    return cw.toByteArray();
}

From source file:org.lanternpowered.server.event.filter.delegate.AfterCauseFilterSourceDelegate.java

License:MIT License

@Override
protected void insertTransform(MethodVisitor mv, Parameter param, Class<?> targetType, int local) {
    mv.visitVarInsn(ALOAD, local);//from  w ww.  j a v a  2 s  . co  m
    Label failure = new Label();
    Label success = new Label();

    mv.visitMethodInsn(INVOKEVIRTUAL, "java/util/Optional", "isPresent", "()Z", false);
    mv.visitJumpInsn(IFEQ, failure);

    // Unwrap the optional
    mv.visitVarInsn(ALOAD, local);
    mv.visitMethodInsn(INVOKEVIRTUAL, "java/util/Optional", "get", "()Ljava/lang/Object;", false);
    mv.visitVarInsn(ASTORE, local);

    mv.visitVarInsn(ALOAD, local);

    mv.visitTypeInsn(INSTANCEOF, Type.getInternalName(targetType));

    if (this.anno.typeFilter().length != 0) {
        mv.visitJumpInsn(IFEQ, failure);
        mv.visitVarInsn(ALOAD, local);
        // For each type we do an instance check and jump to either failure or success if matched
        for (int i = 0; i < this.anno.typeFilter().length; i++) {
            Class<?> filter = this.anno.typeFilter()[i];
            if (i < this.anno.typeFilter().length - 1) {
                mv.visitInsn(DUP);
            }
            mv.visitTypeInsn(INSTANCEOF, Type.getInternalName(filter));
            if (this.anno.inverse()) {
                mv.visitJumpInsn(IFNE, failure);
            } else {
                mv.visitJumpInsn(IFNE, success);
            }
        }
        if (this.anno.inverse()) {
            mv.visitJumpInsn(GOTO, success);
        }
        // If the annotation was not reversed then we fall into failure as no types were matched
    } else {
        mv.visitJumpInsn(IFNE, success);
    }
    mv.visitLabel(failure);
    mv.visitInsn(ACONST_NULL);
    mv.visitInsn(ARETURN);

    mv.visitLabel(success);
}