Android利用MD5码判断字符串是否相等

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 {

@Override
protected 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 Hash
MessageDigest messageDigest = MessageDigest.getInstance("MD5");
messageDigest.update(string.getBytes());
byte messageDigestByteArray[] = messageDigest.digest();
if (messageDigestByteArray == null || messageDigestByteArray.length == 0) {
return "";
}

// Create hexadecimal String
StringBuffer 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 "";
}

}

<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>