de.thetaphi.forbiddenapis.ClassSignature.java Source code

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Here is the source code for de.thetaphi.forbiddenapis.ClassSignature.java

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package de.thetaphi.forbiddenapis;

/*
 * (C) Copyright Uwe Schindler (Generics Policeman) and others.
 * Parts of this work are licensed to the Apache Software Foundation (ASF)
 * under one or more contributor license agreements.
 *
 * 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.
 */

import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.commons.Method;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

/** Utility class that is used to get an overview of all fields and implemented
 * methods of a class. It make the signatures available as Sets. */
final class ClassSignature {
    private ClassReader reader;

    public final boolean isRuntimeClass;
    public final Set<Method> methods;
    public final Set<String> fields;
    public final String className, superName;
    public final String[] interfaces;

    public ClassSignature(final ClassReader classReader, boolean isRuntimeClass, boolean withReader) {
        this.reader = withReader ? classReader : null;
        this.isRuntimeClass = isRuntimeClass;
        this.className = classReader.getClassName();
        this.superName = classReader.getSuperName();
        this.interfaces = classReader.getInterfaces();
        final Set<Method> methods = new HashSet<Method>();
        final Set<String> fields = new HashSet<String>();
        classReader.accept(new ClassVisitor(Opcodes.ASM5) {
            @Override
            public MethodVisitor visitMethod(int access, String name, String desc, String signature,
                    String[] exceptions) {
                final Method m = new Method(name, desc);
                methods.add(m);
                return null;
            }

            @Override
            public FieldVisitor visitField(int access, String name, String desc, String signature, Object value) {
                fields.add(name);
                return null;
            }
        }, ClassReader.SKIP_CODE | ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES);
        this.methods = Collections.unmodifiableSet(methods);
        this.fields = Collections.unmodifiableSet(fields);
    }

    public ClassReader getReader() {
        if (reader == null)
            throw new IllegalStateException("'" + Type.getObjectType(className).getClassName()
                    + "' has no ClassReader, because it was already checked or is only loaded as related class.");
        try {
            return reader;
        } finally {
            reader = null;
        }
    }
}