Here you can find the source of hasClassEntry(JarFile jarFile, String className)
private static boolean hasClassEntry(JarFile jarFile, String className)
//package com.java2s; /******************************************************************************* * Copyright 2011 Google Inc. All Rights Reserved. * * 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 * * 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./*from w w w . j a v a 2 s. co m*/ *******************************************************************************/ import java.util.jar.JarFile; public class Main { private static boolean hasClassEntry(JarFile jarFile, String className) { String path = className.replace('.', '/') + ".class"; return jarFile.getEntry(path) != null; } }