Android利用MD5码判断字符串是不是相等

Android利用MD5码判断字符串是否相等

MainActivity如下:

package cc.testmd5;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException;import android.os.Bundle;import android.app.Activity;/** * Demo描述: * 利用MD5判断两个字符串是否相同 *  * MD5:消息摘要算法(Message Digest Algorithm) * MD5是常用的加密算法,常用于校验信息完整或者两次消息是否一致 *  * 备注说明: * 1 hexadecimal 十六进制 * 2 注意方法:String java.lang.Integer.toHexString(int i) *   Converts the specified integer into its hexadecimal string representation. *   The returned string is a concatenation of characters from '0' to '9' and 'a' to 'f'. *   将整型转换为十六进制 *  */public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);String firstMD5=getMD5("NBA");String secondMD5=getMD5("NBA");System.out.println("firstMD5="+firstMD5+",firstMD5.length()="+firstMD5.length());System.out.println("secondMD5="+secondMD5+",secondMD5.length()="+secondMD5.length());}private String getMD5(String string) {try {// Create MD5 HashMessageDigest messageDigest = MessageDigest.getInstance("MD5");messageDigest.update(string.getBytes());byte messageDigestByteArray[] = messageDigest.digest();if (messageDigestByteArray == null || messageDigestByteArray.length == 0) {return "";}// Create hexadecimal StringStringBuffer hexadecimalStringBuffer = new StringBuffer();int length = messageDigestByteArray.length;for (int i = 0; i < length; i++){hexadecimalStringBuffer.append(Integer.toHexString(0xFF & messageDigestByteArray[i]));}return hexadecimalStringBuffer.toString();} catch (NoSuchAlgorithmException e) {e.printStackTrace();}return "";}}

main.xml如下:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"   >    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="测试Android的MD5码"        android:layout_centerInParent="true"    /></RelativeLayout>