com.develorium.metracer.asm.MetracerClassVisitor.java Source code

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Here is the source code for com.develorium.metracer.asm.MetracerClassVisitor.java

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/*
 * Copyright 2015-2016 Michael Kocherov
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.develorium.metracer.asm;

import java.util.*;
import java.util.regex.*;
import org.objectweb.asm.*;
import org.objectweb.asm.tree.*;
import com.develorium.metracer.*;

public class MetracerClassVisitor extends ClassVisitor {
    private boolean isChanged = false;
    private boolean hasSlf4Logger = false;
    private String className = null;
    private ClassLoader loader = null;
    private Patterns patterns = null;
    private ClassNode parsedClass = null;

    public MetracerClassVisitor(ClassVisitor theClassVisitor, ClassLoader theLoader, Patterns thePatterns,
            ClassNode theParsedClass) {
        super(Opcodes.ASM5, theClassVisitor);
        loader = theLoader;
        patterns = thePatterns;
        parsedClass = theParsedClass;
    }

    @Override
    public void visit(int theVersion, int theAccess, String theClassName, String theSignature,
            String theSuperClassName, String[] theInterfaces) {
        cv.visit(theVersion, theAccess, theClassName, theSignature, theSuperClassName, theInterfaces);
        className = theClassName;
    }

    @Override
    public FieldVisitor visitField(int theAccess, String theName, String theDescription, String theSignature,
            Object theValue) {
        FieldVisitor rv = super.visitField(theAccess, theName, theDescription, theSignature, theValue);

        if (!hasSlf4Logger)
            hasSlf4Logger = theDescription.equals("Lorg/slf4j/Logger;");

        return rv;
    }

    @Override
    public MethodVisitor visitMethod(int theAccess, String theName, String theDescription, String theSignature,
            String[] theExceptions) {
        MethodVisitor methodVisitor = cv.visitMethod(theAccess, theName, theDescription, theSignature,
                theExceptions);
        String classNameWithDots = className.replace("/", ".");

        if (!patterns.isPatternMatched(classNameWithDots, theName))
            return methodVisitor;

        List<MethodNode> methods = parsedClass.methods;
        MethodNode method = null;

        for (MethodNode m : methods) {
            if (m.name.equals(theName) && m.desc.equals(theDescription)) {
                method = m;
                break;
            }
        }

        sayAboutInstrumentation(classNameWithDots, theName, theDescription);
        methodVisitor = new PatternMatchedMethodMutator(className, method, api, methodVisitor, theAccess, theName,
                theDescription, patterns.getStackTraceMode().isEnabled());
        patterns.registerInstrumentedMethod(loader, classNameWithDots, theName + theDescription);
        isChanged = true;
        return methodVisitor;
    }

    public boolean getIsChanged() {
        return isChanged;
    }

    public boolean getHasSlf4Logger() {
        return hasSlf4Logger;
    }

    private static void sayAboutInstrumentation(String theClassName, String theMethodName,
            String theMethodDescription) {
        if (!com.develorium.metracer.Runtime.isVerbose)
            return;

        Type[] argumentTypes = Type.getArgumentTypes(theMethodDescription);
        StringBuilder argumentsInfo = null;

        if (argumentTypes.length > 0) {
            argumentsInfo = new StringBuilder();

            for (int i = 0; i < argumentTypes.length; ++i) {
                if (i > 0)
                    argumentsInfo.append(", ");

                argumentsInfo.append(argumentTypes[i].getClassName());
            }
        }

        com.develorium.metracer.Runtime.say(String.format("Instrumenting %s::%s(%s)", theClassName, theMethodName,
                argumentsInfo != null ? argumentsInfo.toString() : ""));
    }
}