src/test/java/org/apache/bcel/EnclosingMethodAttributeTestCase.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.bcel;

import java.io.File;
import java.io.IOException;

import org.apache.bcel.classfile.Attribute;
import org.apache.bcel.classfile.ConstantPool;
import org.apache.bcel.classfile.EnclosingMethod;
import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.util.SyntheticRepository;
import org.junit.Assert;

public class EnclosingMethodAttributeTestCase extends AbstractTestCase
{
    /**
     * Verify for an inner class declared inside the 'main' method that the
     * enclosing method attribute is set correctly.
     */
    public void testCheckMethodLevelNamedInnerClass()
            throws ClassNotFoundException
    {
        final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.AttributeTestClassEM01$1S");
        final ConstantPool pool = clazz.getConstantPool();
        final Attribute[] encMethodAttrs = findAttribute("EnclosingMethod", clazz);
        assertTrue("Expected 1 EnclosingMethod attribute but found "
                + encMethodAttrs.length, encMethodAttrs.length == 1);
        final EnclosingMethod em = (EnclosingMethod) encMethodAttrs[0];
        final String enclosingClassName = em.getEnclosingClass().getBytes(pool);
        final String enclosingMethodName = em.getEnclosingMethod().getName(pool);
        assertTrue(
                "Expected class name to be '"+PACKAGE_BASE_SIG+"/data/AttributeTestClassEM01' but was "
                        + enclosingClassName, enclosingClassName
                        .equals(PACKAGE_BASE_SIG+"/data/AttributeTestClassEM01"));
        assertTrue("Expected method name to be 'main' but was "
                + enclosingMethodName, enclosingMethodName.equals("main"));
    }

    /**
     * Verify for an inner class declared at the type level that the
     * EnclosingMethod attribute is set correctly (i.e. to a null value)
     */
    public void testCheckClassLevelNamedInnerClass()
            throws ClassNotFoundException
    {
        final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.AttributeTestClassEM02$1");
        final ConstantPool pool = clazz.getConstantPool();
        final Attribute[] encMethodAttrs = findAttribute("EnclosingMethod", clazz);
        assertTrue("Expected 1 EnclosingMethod attribute but found "
                + encMethodAttrs.length, encMethodAttrs.length == 1);
        final EnclosingMethod em = (EnclosingMethod) encMethodAttrs[0];
        final String enclosingClassName = em.getEnclosingClass().getBytes(pool);
        assertTrue(
                "The class is not within a method, so method_index should be null, but it is "
                        + em.getEnclosingMethodIndex(), em
                        .getEnclosingMethodIndex() == 0);
        assertTrue(
                "Expected class name to be '"+PACKAGE_BASE_SIG+"/data/AttributeTestClassEM02' but was "
                        + enclosingClassName, enclosingClassName
                        .equals(PACKAGE_BASE_SIG+"/data/AttributeTestClassEM02"));
    }

    /**
     * Check that we can save and load the attribute correctly.
     */
    public void testAttributeSerializtion() throws ClassNotFoundException,
            IOException
    {
        final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.AttributeTestClassEM02$1");
        final ConstantPool pool = clazz.getConstantPool();
        final Attribute[] encMethodAttrs = findAttribute("EnclosingMethod", clazz);
        assertTrue("Expected 1 EnclosingMethod attribute but found "
                + encMethodAttrs.length, encMethodAttrs.length == 1);
        // Write it out
        final File tfile = createTestdataFile("AttributeTestClassEM02$1.class");
        clazz.dump(tfile);
        // Read in the new version and check it is OK
        final SyntheticRepository repos2 = createRepos(".");
        final JavaClass clazz2 = repos2.loadClass("AttributeTestClassEM02$1");
        Assert.assertNotNull(clazz2); // Use the variable to avoid a warning
        final EnclosingMethod em = (EnclosingMethod) encMethodAttrs[0];
        final String enclosingClassName = em.getEnclosingClass().getBytes(pool);
        assertTrue(
                "The class is not within a method, so method_index should be null, but it is "
                        + em.getEnclosingMethodIndex(), em
                        .getEnclosingMethodIndex() == 0);
        assertTrue(
                "Expected class name to be '"+PACKAGE_BASE_SIG+"/data/AttributeTestClassEM02' but was "
                        + enclosingClassName, enclosingClassName
                        .equals(PACKAGE_BASE_SIG+"/data/AttributeTestClassEM02"));
        tfile.deleteOnExit();
    }
}