MD5算法[ java 实现]

 Java代码

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5 {

/**
 * @param args
 */
public static void main(String[] args) {
String str = "abc123";
System.out.println(MD5.getMD5Str(str));
}

private static String getMD5Str(String str) {
MessageDigest messageDigest = null;

try {
messageDigest = MessageDigest.getInstance("MD5");

messageDigest.reset();

messageDigest.update(str.getBytes("UTF-8"));
} catch (NoSuchAlgorithmException e) {
System.out.println("NoSuchAlgorithmException caught!");
System.exit(-1);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}

byte[] byteArray = messageDigest.digest();

StringBuffer md5StrBuff = new StringBuffer();

for (int i = 0; i < byteArray.length; i++) {
if (Integer.toHexString(0xFF & byteArray[i]).length() == 1)
md5StrBuff.append("0").append(
Integer.toHexString(0xFF & byteArray[i]));
else
md5StrBuff.append(Integer.toHexString(0xFF & byteArray[i]));
}

return md5StrBuff.toString();
}
}

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5 {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		String str = "abc123";
		System.out.println(MD5.getMD5Str(str));
	}

	private static String getMD5Str(String str) {
		MessageDigest messageDigest = null;

		try {
			messageDigest = MessageDigest.getInstance("MD5");

			messageDigest.reset();

			messageDigest.update(str.getBytes("UTF-8"));
		} catch (NoSuchAlgorithmException e) {
			System.out.println("NoSuchAlgorithmException caught!");
			System.exit(-1);
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}

		byte[] byteArray = messageDigest.digest();

		StringBuffer md5StrBuff = new StringBuffer();

		for (int i = 0; i < byteArray.length; i++) {
			if (Integer.toHexString(0xFF & byteArray[i]).length() == 1)
				md5StrBuff.append("0").append(
						Integer.toHexString(0xFF & byteArray[i]));
			else
				md5StrBuff.append(Integer.toHexString(0xFF & byteArray[i]));
		}

		return md5StrBuff.toString();
	}
}