Security and Cryptography - Java Examples in a Nutshell - page 130

Example 6−4: Manifest.java (continued)

public static void main(String[] args) throws Exception {
// Set the default values of the command-line arguments
boolean verify = false; // Verify manifest or create one?
String manifestfile = "MANIFEST"; // Manifest file name
String digestAlgorithm = "MD5"; // Algorithm for message digests
String signername = null; // Signer. No sig. by default
String signatureAlgorithm = "DSA"; // Algorithm for digital sig.
String password = null; // Private keys are protected

File keystoreFile = null; // Where are keys stored

String keystoreType = null; // What kind of keystore

String keystorePassword = null; // How to access keystore

List filelist = new ArrayList(); // The files to digest

// Parse the command-line arguments, overriding the defaults above
for(int i = 0; i < args.length; i++) {
if (args[i].equals("-v")) verify = true;
else if (args[i].equals("-m")) manifestfile = args[++i];
else if (args[i].equals("-da") && !verify)
digestAlgorithm = args[++i];
else if (args[i].equals("-s") && !verify)
signername = args[++i];
else if (args[i].equals("-sa") && !verify)
signatureAlgorithm = args[++i];
else if (args[i].equals("-p"))
password = args[++i];
else if (args[i].equals("-keystore"))
keystoreFile = new File(args[++i]);
else if (args[i].equals("-keystoreType"))
keystoreType = args[++i];
else if (args[i].equals("-keystorePassword"))
keystorePassword = args[++i];

else if (!verify) filelist.add(args[i]);
else throw new IllegalArgumentException(args[i]);

}

// If certain arguments weren't supplied, get default values.
if (keystoreFile == null) {
File dir = new File(System.getProperty("user.home"));
keystoreFile = new File(dir, ".keystore");

}
if (keystoreType == null) keystoreType = KeyStore.getDefaultType();
if (keystorePassword == null) keystorePassword = password;

if (!verify && signername != null && password == null) {
System.out.println("Use -p to specify a password.");
return;

}

// Get the keystore we'll use for signing or verifying signatures
// If no password was provided, then assume we won't be dealing with
// signatures, and skip the keystore.
KeyStore keystore = null;
if (keystorePassword != null) {
keystore = KeyStore.getInstance(keystoreType);
InputStream in =
new BufferedInputStream(new FileInputStream(keystoreFile));
keystore.load(in, keystorePassword.toCharArray());