Introduce Digest

[gpl/argeo-slc.git] / runtime / org.argeo.slc.core / src / main / java / org / argeo / slc / core / deploy / DigestCheck.java

diff --git a/runtime/org.argeo.slc.core/src/main/java/org/argeo/slc/core/deploy/DigestCheck.java b/runtime/org.argeo.slc.core/src/main/java/org/argeo/slc/core/deploy/DigestCheck.java
new file mode 100644 (file)
index 0000000..cc0e2ff
--- /dev/null
+++ b/runtime/org.argeo.slc.core/src/main/java/org/argeo/slc/core/deploy/DigestCheck.java
@@ -0,0 +1,129 @@
+package org.argeo.slc.core.deploy;
+
+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;
+
+import org.apache.commons.codec.binary.Hex;
+import org.apache.commons.io.IOUtils;
+import org.argeo.slc.SlcException;
+import org.springframework.core.io.Resource;
+
+public class DigestCheck {
+       private static Boolean debug = true;
+       // TODO: make it writable
+       private final static Integer byteBufferCapacity = 100 * 1024;// 100 KB
+
+       public static String digest(String algorithm, Resource resource) {
+               try {
+                       File file = resource.getFile();
+                       return digest(algorithm, file);
+               } catch (IOException e) {
+                       try {
+                               return digest(algorithm, resource.getInputStream());
+                       } catch (IOException e1) {
+                               throw new SlcException("Cannot digest " + resource
+                                               + " 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 = Hex.encodeHexString(checksum);
+                       return res;
+               } catch (Exception e) {
+                       throw new SlcException("Cannot digest with algorithm " + algorithm,
+                                       e);
+               } finally {
+                       IOUtils.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 SlcException("Cannot digest " + file + " with algorithm "
+                                       + algorithm, e);
+               } finally {
+                       IOUtils.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 = Hex.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 SlcException("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));
+               }
+       }
+
+}