ClassInstrumenter.java

/*******************************************************************************
 * Copyright (c) 2009, 2025 Mountainminds GmbH & Co. KG and Contributors
 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *    Marc R. Hoffmann - initial API and implementation
 *
 *******************************************************************************/
package org.jacoco.core.internal.instr;

import org.jacoco.core.internal.flow.ClassProbesVisitor;
import org.jacoco.core.internal.flow.MethodProbesVisitor;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.MethodVisitor;

/**
 * Adapter that instruments a class for coverage tracing.
 */
public class ClassInstrumenter extends ClassProbesVisitor {

    private final IProbeArrayStrategy probeArrayStrategy;

    private String className;

    /**
     * Emits an instrumented version of this class to the given class visitor.
     *
     * @param probeArrayStrategy
     *            this strategy will be used to access the probe array
     * @param cv
     *            next delegate in the visitor chain will receive the
     *            instrumented class
     */
    public ClassInstrumenter(final IProbeArrayStrategy probeArrayStrategy,
            final ClassVisitor cv) {
        super(cv);
        this.probeArrayStrategy = probeArrayStrategy;
    }

    @Override
    public void visit(final int version, final int access, final String name,
            final String signature, final String superName,
            final String[] interfaces) {
        this.className = name;
        super.visit(version, access, name, signature, superName, interfaces);
    }

    @Override
    public FieldVisitor visitField(final int access, final String name,
            final String desc, final String signature, final Object value) {
        InstrSupport.assertNotInstrumented(name, className);
        return super.visitField(access, name, desc, signature, value);
    }

    @Override
    public MethodProbesVisitor visitMethod(final int access, final String name,
            final String desc, final String signature,
            final String[] exceptions) {

        InstrSupport.assertNotInstrumented(name, className);

        final MethodVisitor mv = cv.visitMethod(access, name, desc, signature,
                exceptions);

        if (mv == null) {
            return null;
        }
        final MethodVisitor frameEliminator = new DuplicateFrameEliminator(mv);
        final ProbeInserter probeVariableInserter = new ProbeInserter(access,
                name, desc, frameEliminator, probeArrayStrategy);
        return new MethodInstrumenter(probeVariableInserter,
                probeVariableInserter);
    }

    @Override
    public void visitTotalProbeCount(final int count) {
        probeArrayStrategy.addMembers(cv, count);
    }

}