Remove APIs from utils

[lgpl/argeo-commons.git] / org.argeo.util / src / org / argeo / util / DigestUtils.java

diff --git a/org.argeo.util/src/org/argeo/util/DigestUtils.java b/org.argeo.util/src/org/argeo/util/DigestUtils.java
new file mode 100644 (file)
index 0000000..52cbc5d
--- /dev/null
+++ b/org.argeo.util/src/org/argeo/util/DigestUtils.java
@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2007-2012 Argeo GmbH
+ *
+ * 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.
+ */
+package org.argeo.util;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.channels.FileChannel;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+/** Utilities around cryptographic digests */
+public class DigestUtils {
+       private static Boolean debug = true;
+       // TODO: make it writable
+       private final static Integer byteBufferCapacity = 100 * 1024;// 100 KB
+
+       public static String digest(String algorithm, byte[] bytes) {
+               try {
+                       MessageDigest digest = MessageDigest.getInstance(algorithm);
+                       digest.update(bytes);
+                       byte[] checksum = digest.digest();
+                       String res = encodeHexString(checksum);
+                       return res;
+               } catch (Exception e) {
+                       throw new UtilsException("Cannot digest with algorithm " + algorithm, e);
+               }
+       }
+
+       public static String digest(String algorithm, InputStream in) {
+               try {
+                       MessageDigest digest = MessageDigest.getInstance(algorithm);
+                       // ReadableByteChannel channel = Channels.newChannel(in);
+                       // ByteBuffer bb = ByteBuffer.allocateDirect(byteBufferCapacity);
+                       // while (channel.read(bb) > 0)
+                       // digest.update(bb);
+                       byte[] buffer = new byte[byteBufferCapacity];
+                       int read = 0;
+                       while ((read = in.read(buffer)) > 0) {
+                               digest.update(buffer, 0, read);
+                       }
+
+                       byte[] checksum = digest.digest();
+                       String res = encodeHexString(checksum);
+                       return res;
+               } catch (Exception e) {
+                       throw new UtilsException("Cannot digest with algorithm " + algorithm, e);
+               } finally {
+                       StreamUtils.closeQuietly(in);
+               }
+       }
+
+       public static String digest(String algorithm, File file) {
+               FileInputStream fis = null;
+               FileChannel fc = null;
+               try {
+                       fis = new FileInputStream(file);
+                       fc = fis.getChannel();
+
+                       // Get the file's size and then map it into memory
+                       int sz = (int) fc.size();
+                       ByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, sz);
+                       return digest(algorithm, bb);
+               } catch (IOException e) {
+                       throw new UtilsException("Cannot digest " + file + " with algorithm " + algorithm, e);
+               } finally {
+                       StreamUtils.closeQuietly(fis);
+                       if (fc.isOpen())
+                               try {
+                                       fc.close();
+                               } catch (IOException e) {
+                                       // silent
+                               }
+               }
+       }
+
+       protected static String digest(String algorithm, ByteBuffer bb) {
+               long begin = System.currentTimeMillis();
+               try {
+                       MessageDigest digest = MessageDigest.getInstance(algorithm);
+                       digest.update(bb);
+                       byte[] checksum = digest.digest();
+                       String res = encodeHexString(checksum);
+                       long end = System.currentTimeMillis();
+                       if (debug)
+                               System.out.println((end - begin) + " ms / " + ((end - begin) / 1000) + " s");
+                       return res;
+               } catch (NoSuchAlgorithmException e) {
+                       throw new UtilsException("Cannot digest with algorithm " + algorithm, e);
+               }
+       }
+
+       public static void main(String[] args) {
+               File file;
+               if (args.length > 0)
+                       file = new File(args[0]);
+               else {
+                       System.err.println("Usage: <file> [<algorithm>]" + " (see http://java.sun.com/j2se/1.5.0/"
+                                       + "docs/guide/security/CryptoSpec.html#AppA)");
+                       return;
+               }
+
+               if (args.length > 1) {
+                       String algorithm = args[1];
+                       System.out.println(digest(algorithm, file));
+               } else {
+                       String algorithm = "MD5";
+                       System.out.println(algorithm + ": " + digest(algorithm, file));
+                       algorithm = "SHA";
+                       System.out.println(algorithm + ": " + digest(algorithm, file));
+                       algorithm = "SHA-256";
+                       System.out.println(algorithm + ": " + digest(algorithm, file));
+                       algorithm = "SHA-512";
+                       System.out.println(algorithm + ": " + digest(algorithm, file));
+               }
+       }
+
+       final private static char[] hexArray = "0123456789ABCDEF".toCharArray();
+
+       /**
+        * From
+        * http://stackoverflow.com/questions/9655181/how-to-convert-a-byte-array-to
+        * -a-hex-string-in-java
+        */
+       private static String encodeHexString(byte[] bytes) {
+               char[] hexChars = new char[bytes.length * 2];
+               for (int j = 0; j < bytes.length; j++) {
+                       int v = bytes[j] & 0xFF;
+                       hexChars[j * 2] = hexArray[v >>> 4];
+                       hexChars[j * 2 + 1] = hexArray[v & 0x0F];
+               }
+               return new String(hexChars);
+       }
+
+}