/**
 * 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.cxf.common.util;

import java.io.*;
import java.net.URL;
import java.util.*;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;
import java.util.zip.ZipInputStream;

public final class JarResource {

    public List<String> getJarContents(URL jarLocation) throws IOException {
        return getJarContents(jarLocation.openStream());
    }

    public List<String> getJarContents(InputStream is) throws IOException {
        return load(is);
    }
    
    public List<String> getJarContents(String jarLocation) throws IOException {
        return getJarContents(new File(jarLocation));
    }

    public List<String> getJarContents(File jarFile) throws IOException {
        return load(jarFile);
    }

    private List<String> load(File jarFile) throws IOException {
        List<String> jarContents = new ArrayList<String>();
        try {
            ZipFile zf = new ZipFile(jarFile);
            for (Enumeration<? extends ZipEntry> e = zf.entries(); e.hasMoreElements();) {
                ZipEntry ze = e.nextElement();
                if (ze.isDirectory()) {
                    continue;
                }
                jarContents.add(ze.getName());
            }
        } catch (NullPointerException e) {
            System.out.println("done.");
        } catch (ZipException ze) {
            ze.printStackTrace();
        }
        return jarContents;
    }
    
    private List<String> load(InputStream is) throws IOException {
        List<String> jarContents = new ArrayList<String>();
        try {
            ZipInputStream zis = new ZipInputStream(is);
            ZipEntry ze = zis.getNextEntry();
            while (ze != null) {
                if (ze.isDirectory()) {
                    continue;
                }
                jarContents.add(ze.getName());
                ze = zis.getNextEntry();
            }
        } catch (NullPointerException e) {
            System.out.println("done.");
        }

        return jarContents;
    }
}
