com.netease.stream.util.Md5Utils Maven / Gradle / Ivy
package com.netease.stream.util;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import org.apache.commons.codec.binary.Hex;
/**
* Utility methods for computing MD5 sums.
*/
public class Md5Utils {
/**
* Computes the MD5 hash of the data in the given input stream and returns it as an array of
* bytes.
*
* @param is Needed to compute with MD5.
* @return byte[] Computed with MD5.
* @throws NoSuchAlgorithmException NoSuchAlgorithmException.
* @throws IOException IOException.
*/
public static byte[] computeMD5Hash(InputStream is) throws NoSuchAlgorithmException,
IOException {
BufferedInputStream bis = new BufferedInputStream(is);
try {
MessageDigest messageDigest = MessageDigest.getInstance("MD5");
byte[] buffer = new byte[16384];
int bytesRead = -1;
while ((bytesRead = bis.read(buffer, 0, buffer.length)) != -1) {
messageDigest.update(buffer, 0, bytesRead);
}
return messageDigest.digest();
} finally {
try {
bis.close();
} catch (Exception e) {
System.err.println("Unable to close input stream of hash candidate: " + e);
}
}
}
/**
* Computes the MD5 hash of the given data and returns it as an array of bytes.
*
* @param data Needed to compute with MD5.
* @return byte[] Computed with MD5.
* @throws NoSuchAlgorithmException NoSuchAlgorithmException.
* @throws IOException IOException.
*/
public static byte[] computeMD5Hash(byte[] data) throws NoSuchAlgorithmException, IOException {
return computeMD5Hash(new ByteArrayInputStream(data));
}
/**
* Get hex string
*
* @param raw Encoded hex.
* @return String Encoded hex.
*/
public static String getHex(byte[] raw) {
if (raw == null) {
return "null";
}
return new String(Hex.encodeHex(raw));
}
}