比较两个文件是否相同,获取文件MD5值, HandlerThread 使用

比较两个文件是否相同,获取文件MD5值
通过adb 或者串口 的 md5 指令获取某个文件的MD5 值

adb shell

cd storage/sdcard0/  

root@g0003ah:/storage/sdcard0 # md5 tsp.jar

5cbfb75d1db4121b4b9e3a00dde49a18  tsp.jar   // 此值即为这个文件的md5值

也可以比较两个文件的md5

root@g0003ah:/storage/sdcard0 # md5 tsp.jar  t1sp.jar                          

5cbfb75d1db4121b4b9e3a00dde49a18  tsp.jar

5cbfb75d1db4121b4b9e3a00dde49a18  t1sp.jar

可以看出这个两个jar是同一个jar

用串口也可以.打开串口的方法

cd  /dev

sudo minicom -D ttyUSB*

//输入密码

指令如上

root@g0003ah:/mnt/sdcard0 # md5 tsp.jar                                        

5cbfb75d1db4121b4b9e3a00dde49a18  tsp.jar

Application 中通过utils 获取文件的md5 值

随便写个demo

文件目录为:/mnt/sdcard0/md5.txt

MainActivity:

package com.tan.md5;

import android.os.Handler;
import android.os.HandlerThread;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import com.tan.md5.utils.Utils;

public class MainActivity extends AppCompatActivity {
private static final String TAG = MainActivity.class.getSimpleName();

private TextView vFileMD5Text;

private Button vFileMD5Btn;
private String mFilePath = "/mnt/sdcard0/md5.txt";

private static final HandlerThread sWorkerThread = new HandlerThread("FileMD5-thread");

static {
sWorkerThread.start();
}

/**
* sWorker队列执行任务，post执行完做下一个post
*/
protected static final Handler sWorker = new Handler(sWorkerThread.getLooper());

private static final int MESSAGE_FILE_MD5 = 100;

private Handler mHandler = new Handler() {

@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what) {
case MESSAGE_FILE_MD5:
vFileMD5Text.setText((String)msg.obj);
break;
default:
break;
}
}
};

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

initView();
initListener();
}

private void initView() {
vFileMD5Text = (TextView) findViewById(R.id.tv_file1_md5);
vFileMD5Btn = (Button) findViewById(R.id.btn_File1_MD5);
}

private void initListener() {
vFileMD5Btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getFileMD5();
}
});
}

private void getFileMD5() {
sWorker.post(new Runnable() {
@Override
public void run() {
String strMD5 = Utils.getMd5sum(mFilePath);
Message msg = mHandler.obtainMessage();
msg.what = MESSAGE_FILE_MD5;
msg.obj = strMD5;
mHandler.sendMessage(msg);
}
});
}

}

Utils:

package com.tan.md5.utils;

import android.util.Log;

import java.io.FileInputStream;
import java.io.InputStream;
import java.security.MessageDigest;

/**
* Created by pateo on 18-2-6.
*/

public class Utils {
private static final String TAG = Utils.class.getSimpleName();

public static String getMd5sum(String filename) {
InputStream fis;
byte[] buffer = new byte[1024];
int numRead = 0;
MessageDigest md5;
try {
fis = new FileInputStream(filename);
md5 = MessageDigest.getInstance("MD5");
while ((numRead = fis.read(buffer)) > 0) {
md5.update(buffer, 0, numRead);
}
fis.close();
return toHexString(md5.digest());
} catch (Exception e) {
return null;
}
}

public static String toHexString(byte[] b) {
Log.d(TAG , "--toHexString --b=" + b.length + "---b=" + b.toString() );
char HEX_DIGITS[] = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};

StringBuilder sb = new StringBuilder(b.length * 2);
for (int i = 0; i < b.length; i++) {
sb.append(HEX_DIGITS[(b[i] & 0xf0) >> 4]);
sb.append(HEX_DIGITS[b[i] & 0x0f]);
}
Log.d(TAG , "--toHexString -sb=" + sb.toString() );
return sb.toString();
}

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.tan.md5.MainActivity"
android:padding="30dp"
android:orientation="vertical">

<TextView
android:id="@+id/tv_file1_md5"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

<TextView
android:id="@+id/tv_file2_md5"
android:layout_width="wrap_content"
android:layout_marginTop="30px"
android:layout_height="wrap_content" />

<Button
android:id="@+id/btn_File1_MD5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="获取MD5"/>

</LinearLayout>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.tan.md5">

<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

</manifest>