文件复制与下载

package com.example.administrator.www;

import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;

import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;

public class MainActivity extends AppCompatActivity {

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

        //文件复制
        //将SD卡根目录下的Environment.pptx文件复制到其他目录
        //1.将文件复制到SD下的openstack目录

        //源文件
        File sourceFile = new File(Environment.getExternalStorageDirectory(), "Environment.pptx");
        Log.e("源文件路径", sourceFile.getAbsolutePath());

        //目标文件
        File targetDir = new File(getExternalFilesDir(null), "swift");
        if (!targetDir.exists()) {
            targetDir.mkdir();
        }
        File targetFile = new File(targetDir, "Environment.pptx");
        if (!targetFile.exists()) try {
            targetFile.createNewFile();
        } catch (IOException e) {
            e.printStackTrace();
        }
        Log.e("目标文件路径", targetFile.getAbsolutePath());


        //蚂蚁搬家
        try {

            //文件输入流
            FileInputStream inputStream = new FileInputStream(sourceFile);


            //文件输出流
            FileOutputStream outputStream = new FileOutputStream(targetFile);

            //每次流读取的长度
            int length = 0;//范围0~1024
            byte[] bytes = new byte[1024];//每次读取数据流中数据是先缓存到数组中

            while ((length = inputStream.read(bytes)) != -1) {//读
                outputStream.write(bytes, 0, length);
            }

            inputStream.close();
            outputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

        //文件下载
        //文件下载，下载到SD卡的Download目录下
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    URL url = new URL("http://10.32.9.10:8081/swift/Environment.pptx");
                    URLConnection connection = url.openConnection();//连接服务器
                    //强转为HTTP类型的URLConnection
                    HttpURLConnection httpURLConnection = (HttpURLConnection) connection;
                    httpURLConnection.setRequestMethod("GET");//设置请求方式
                    //验证是否请求成功。200代表成功，404代表服务器项目资源找不到
                    if (200 == httpURLConnection.getResponseCode()) {
                        //服务器返回给我们的IO数据流
                        InputStream inputStream = httpURLConnection.getInputStream();

                        //目标文件,第一句话是SD卡，引号是目录
                        File targetDir = new File(Environment.getExternalStorageDirectory(), "openstack");
                        if (!targetDir.exists()) {
                            targetDir.mkdir();
                        }
                        File targetFile = new File(targetDir, "Environment.pptx");
                        if (!targetFile.exists()) try {
                            targetFile.createNewFile();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                        //文件输出流
                        FileOutputStream outputStream = new FileOutputStream(targetFile);

                        //每次流读取的长度
                        int length = 0;//范围0~1024
                        byte[] bytes = new byte[1024];//每次读取数据流中数据是先缓存到数组中

                        while ((length = inputStream.read(bytes)) != -1) {//读
                            outputStream.write(bytes, 0, length);
                        }

                        inputStream.close();
                        outputStream.close();


                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }

            ;
        }).start();


    }

}