test.java

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * 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 java.util.*;
import java.lang.*;
import java.io.*;
import java.security.cert.Certificate;
import java.util.jar.JarFile;
import java.util.jar.JarEntry;
import java.util.jar.Attributes;
import java.util.jar.Manifest;

class test
{
	private static final String ANDROID_MANIFEST_FILENAME = "AndroidManifest.xml";
	public static void main (String[] args) throws java.lang.Exception
	{
		JarFile jarFile = new JarFile("test.apk");
		Enumeration<JarEntry> entries = jarFile.entries();
		final Manifest manifest = jarFile.getManifest();
		while (entries.hasMoreElements()) {
			 final JarEntry je = entries.nextElement();
                    if (je.isDirectory()) continue;

                    final String name = je.getName();

                    if (name.startsWith("META-INF/"))
                        continue;
		    if (ANDROID_MANIFEST_FILENAME.equals(name)) {
                        final Attributes attributes = manifest.getAttributes(name);
                        //pkg.manifestDigest = ManifestDigest.fromAttributes(attributes);
                    }
		    final Certificate[] certs = loadCertificates(jarFile, je);
		    System.out.println(" entry " + je.getName()
                                + ": certs=" + certs[0] + " ("
                               + (certs != null ? certs.length : 0) + ")");
	    }
	}
	
	private static Certificate[] loadCertificates(JarFile jarFile, JarEntry entry)
            throws Exception {
        InputStream is = null;
        try {
            // We must read the stream for the JarEntry to retrieve
            // its certificates.
            is = jarFile.getInputStream(entry);
            readFullyIgnoringContents(is);
            return entry.getCertificates();
        } catch (IOException | RuntimeException e) {
            throw new Exception("Failed reading " + entry.getName() + " in " + jarFile, e);
        } finally {
            is.close();
        }
    }
        public static long readFullyIgnoringContents(InputStream in) throws IOException {
        byte[] buffer = new byte[4096];
        int n = 0;
        int count = 0;
        while ((n = in.read(buffer, 0, buffer.length)) != -1) {
            count += n;
        }
        return count;
    }
}