org.jacoco.core.internal.flow.ClassProbesAdapter.java Source code

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Here is the source code for org.jacoco.core.internal.flow.ClassProbesAdapter.java

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/*******************************************************************************
 * Copyright (c) 2009, 2013 Mountainminds GmbH & Co. KG and Contributors
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Marc R. Hoffmann - initial API and implementation
 *    
 *******************************************************************************/
package org.jacoco.core.internal.flow;

import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

/**
 * A {@link org.objectweb.asm.ClassVisitor} that calculates probes for every
 * method.
 */
public class ClassProbesAdapter extends ClassVisitor implements IProbeIdGenerator {

    private static final MethodProbesVisitor EMPTY_METHOD_PROBES_VISITOR;

    static {
        class Impl extends MethodProbesVisitor {

            @Override
            public void visitProbe(final int probeId) {
                // nothing to do
            }

            @Override
            public void visitJumpInsnWithProbe(final int opcode, final Label label, final int probeId) {
                // nothing to do
            }

            @Override
            public void visitInsnWithProbe(final int opcode, final int probeId) {
                // nothing to do
            }

            @Override
            public void visitTableSwitchInsnWithProbes(final int min, final int max, final Label dflt,
                    final Label[] labels) {
                // nothing to do
            }

            @Override
            public void visitLookupSwitchInsnWithProbes(final Label dflt, final int[] keys, final Label[] labels) {
                // nothing to do
            }
        }
        EMPTY_METHOD_PROBES_VISITOR = new Impl();
    }

    private static class ProbeCounter implements IProbeIdGenerator {
        int count = 0;

        public int nextId() {
            return count++;
        }
    }

    private final ClassProbesVisitor cv;

    private int counter = 0;

    private boolean interfaceType;

    /**
     * Creates a new adapter that delegates to the given visitor.
     * 
     * @param cv
     *            instance to delegate to
     */
    public ClassProbesAdapter(final ClassProbesVisitor cv) {
        super(Opcodes.ASM4, cv);
        this.cv = cv;
    }

    @Override
    public void visit(final int version, final int access, final String name, final String signature,
            final String superName, final String[] interfaces) {
        interfaceType = (access & Opcodes.ACC_INTERFACE) != 0;
        super.visit(version, access, name, signature, superName, interfaces);
    }

    @Override
    public final MethodVisitor visitMethod(final int access, final String name, final String desc,
            final String signature, final String[] exceptions) {
        final MethodProbesVisitor methodProbes;
        final MethodProbesVisitor mv = cv.visitMethod(access, name, desc, signature, exceptions);
        if (mv == null) {
            // We need to visit the method in any case, otherwise probe ids
            // are not reproducible
            methodProbes = EMPTY_METHOD_PROBES_VISITOR;
        } else {
            methodProbes = mv;
        }
        return new MethodSanitizer(null, access, name, desc, signature, exceptions) {

            @Override
            public void visitEnd() {
                super.visitEnd();
                LabelFlowAnalyzer.markLabels(this);
                if (interfaceType) {
                    final ProbeCounter probeCounter = new ProbeCounter();
                    final MethodProbesAdapter adapter = new MethodProbesAdapter(EMPTY_METHOD_PROBES_VISITOR,
                            probeCounter);
                    // We do not use the accept() method as ASM resets labels
                    // after every call to accept()
                    instructions.accept(adapter);
                    cv.visitTotalProbeCount(probeCounter.count);
                }
                this.accept(new MethodProbesAdapter(methodProbes, ClassProbesAdapter.this));
            }
        };
    }

    @Override
    public void visitEnd() {
        if (!interfaceType) {
            cv.visitTotalProbeCount(counter);
        }
        super.visitEnd();
    }

    // === IProbeIdGenerator ===

    public int nextId() {
        return counter++;
    }

}