testmsgdigest.java

常用的java控件使用实例源代码

//import java.Security.*;
import java.security.MessageDigest;

public class testMsgDigest {
	public static void main(String[] agrs) {
		testMsgDigest my = new testMsgDigest();
		my.testDigest();
	}
	
	public void testDigest() {
		try {
			String myInfo = "my information";
			java.security.MessageDigest alga = java.security.MessageDigest.getInstance("sha-1");
			alga.update(myInfo.getBytes());
			byte[] digesta = alga.digest();
			System.out.println("本消息摘要是：" + byteZhex(digesta));
			
			java.security.MessageDigest algb = java.security.MessageDigest.getInstance("sha-1");
			algb.update(myInfo.getBytes());
			if(algb.isEqual(digesta,algb.digest())) {
				System.out.println("right!");
			}
			else {
				System.out.println("wrong");
			}
		}
		catch (java.security.NoSuchAlgorithmException ex) {
			System.out.println("非法摘要算法");
		}
		
	}
	
	public String byteZhex(byte[] b) {
		String hs = "";
		String stmp = "";
		for (int n = 0; n < b.length; n++) {
			stmp = (java.lang.Integer.toHexString(b[n] & 0xff));
			if ( stmp.length() == 1) hs = hs + "0" + stmp;
			else hs = hs + stmp;
			if (n < b.length - 1) hs = hs + ":";
			
		}
		return hs.toUpperCase();
	}
}