java IO流练习:文件复制、遍历子目录、复制所有子目录

import org.junit.Test;import java.awt.*;import java.io.*;import java.net.URI;import java.net.URISyntaxException;import java.text.SimpleDateFormat;/** * @author king *         Created by king on 2017/5/19. */public class IOTrain {    //    @Test    public void testTime() {//测试函数运行时间        long start = System.currentTimeMillis();        for (int i = 0; i < 1; i++) {            try {                Thread.sleep(1000);            } catch (InterruptedException e) {                e.printStackTrace();            }        }        long end = System.currentTimeMillis();        SimpleDateFormat sdf = new SimpleDateFormat("s");        System.out.println(sdf.format(end - start));    }    //    @Test    public void createFile() {//创建a.txt        File file = new File("D:\\file\\a.txt");        try {            file.createNewFile();        } catch (IOException e) {            e.printStackTrace();        }    }    //    @Test    public void fileList() {//列出D盘下的所有文件、文件夹        File file = new File("D:");        String[] ss = file.list();        for (String s : ss) System.out.println(s);    }    //    @Test    public void fileList2() {//列出D盘下的所有文件、文件夹        File file = new File("D:");        File[] files = file.listFiles();        for (File f : files) System.out.println(f.getPath());    }    //    @Test    public void makeDir() {//创建文件夹        File file = new File("D:\\file\\44");        file.mkdir();    }    //    @Test    public void testShowAllDir() {//显示D盘下所有的子文件        String path = "D:";        showAllDir(path);    }    public void showAllDir(String path) {        File file = new File(path);        File fs[] = file.listFiles();        for (int i = 0; i < fs.length; i++) {            if (fs[i].isDirectory()) {                try {                    showAllDir(fs[i].getAbsolutePath());                } catch (Exception e) {                }            } else {                System.out.println(fs[i].getAbsolutePath());            }        }    }    //    @Test    public void browseBaidu1() {//用浏览器打开百度        try {            URI uri = new URI("http://www.baidu.com");            Desktop.getDesktop().browse(uri);        } catch (Exception e) {        }    }    //    @Test    public void browseBaidu2() {//用浏览器打开百度，完整版        String webSite = "http://www.baidu.com";        Desktop desktop = Desktop.getDesktop();        if (Desktop.isDesktopSupported() && desktop.isSupported(Desktop.Action.BROWSE)) {            URI uri = null;            try {                uri = new URI(webSite);            } catch (URISyntaxException e) {                e.printStackTrace();            }            try {                desktop.browse(uri);            } catch (IOException e) {                e.printStackTrace();            }        }    }    //    @Test    public void readByte() {// 从文件系统中的某个文件中获得输入字节        try (FileInputStream fs = new FileInputStream("D:\\file\\1.txt")) {            byte[] buffer = new byte[1024];            int n = 0;            while ((n = fs.read(buffer)) != -1) {                System.out.println(new String(buffer));            }        } catch (IOException e) {            e.printStackTrace();        }    }    @Test    public void writeByte() {//FileOutputStream，意为文件输出流，是用于将数据写入File或 FileDescriptor的输出流。        try (FileOutputStream fs = new FileOutputStream("D:\\file\\3.txt")) {            fs.write("哈尔滨".getBytes());        } catch (IOException e) {            e.printStackTrace();        }    }    //    @Test    public void copyByte() {//将1.txt拷贝到2.txt        try (FileOutputStream w = new FileOutputStream("D:\\file\\2.txt");             FileInputStream r = new FileInputStream("D:\\file\\1.txt")) {            byte[] buffer = new byte[1024];            int n = 0;            while ((n = r.read(buffer)) != -1) {                w.write(buffer, 0, n);            }        } catch (IOException e) {            e.printStackTrace();        }    }    //    @Test    public void readChar() {//FileReader类从InputStreamReader类继承而来。该类按字符读取流中数据。        try (Reader reader = new FileReader("D:\\file\\1.txt")) {            char[] buffer = new char[20];            int n = 0;            while ((n = reader.read(buffer)) != -1) {                System.out.println(buffer);            }        } catch (IOException e) {            e.printStackTrace();        }    }    //    @Test    public void writeChar() {//FileWriter类从OutputStreamReader类继承而来。该类按字符向流中写入数据。        try (Writer writer = new FileWriter("D:\\file\\1.txt")) {            writer.write("哈尔滨");        } catch (IOException e) {            e.printStackTrace();        }    }    //    @Test    public void copyChar() {//按字符流将1.txt复制给2.txt        try (FileReader reader = new FileReader("D:\\file\\1.txt");             FileWriter writer = new FileWriter("D:\\file\\2.txt")) {            int n = 0;            char[] buffer = new char[20];            while ((n = reader.read(buffer)) != -1) {                writer.write(buffer, 0, n);            }        } catch (IOException e) {            e.printStackTrace();        }    }    //    @Test    public void FindFileByType() {//查找 *.bat        File file = new File("D:");        File[] find = file.listFiles(new FilenameFilter() {            @Override            public boolean accept(File dir, String name) {                return name.endsWith(".bat");            }        });        for (File f : find) System.out.println(f.getName());    }    //    @Test    public void testCopyAllDir1() {        String readPath = "D:\\file";//源地址        String writePath = "D:\\file2";//目标地址        new File(writePath).mkdirs();        copyAllDir1(readPath, writePath);    }    public void copyAllDir1(String readPath, String writePath) {        File file = new File(readPath);        File[] fs = file.listFiles();        for (int i = 0; i < fs.length; i++) {            try {                if (fs[i].isDirectory()) {                    fs[i].mkdir();                    copyAllDir1(fs[i].getAbsolutePath(), writePath + "\\" + fs[i].getName());                } else {                    System.out.println(fs[i].getAbsolutePath());                }            } catch (Exception e) {            }        }    }    //    @Test    public void testCopyAllDir2() {        String readPath = "D:\\file";//源地址        String writePath = "D:\\file2";//目标地址        new File(writePath).mkdir();        copyAllDir2(readPath, writePath);    }    public void copyAllDir2(String readPath, String writePath) {//将readPath中的所有子文件拷贝到writePath目录下。        //获取当前readPath目录下所有文件、文件夹，并存在fs[] 中        File file = new File(readPath);        File fs[] = file.listFiles();        //fs!=null 排除空指针异常        if (fs != null) {            //遍历当前目录            for (int i = 0; i < fs.length; i++) {                //如果当前对象fs[i]是文件夹，则在目标地址中创建同名的文件夹。                if (fs[i].isDirectory()) {                    new File(writePath + "\\" + fs[i].getName()).mkdir();                    copyAllDir2(fs[i].getPath(), writePath + "\\" + fs[i].getName());                }                //如果当前对象fs[i]是文件，那么按字节拷贝到目标地址。                else {                    try (FileInputStream readFile = new FileInputStream(fs[i].getPath());/*从这里读数据*/                         FileOutputStream writeFile = new FileOutputStream(writePath + "\\" + fs[i].getName()))/*往这里写数据*/ {                        byte[] buffer = new byte[1024];                        int n = 0;                        while ((n = readFile.read(buffer)) != -1) {                            writeFile.write(buffer, 0, n);                        }                    } catch (IOException e) {                        e.printStackTrace();                    }                }            }        }    }//    @Test    public void mergeRandomAccessFile() {//将两个mp3文件合并。RandomAccessFile的唯一父类是Object        try (RandomAccessFile r = new RandomAccessFile("c://1.mp3", "r");             RandomAccessFile w = new RandomAccessFile("c://2.mp3", "rw")) {            byte[] buffer = new byte[1024 * 1024];            w.seek(1024 * 1024);//定位到末尾，MP3 avi            int n = 0;            while ((n = r.read(buffer)) != -1) {                w.write(buffer, 0, n);            }        } catch (Exception e) {            e.printStackTrace();        }    }//    @Test    public void copyRandomAccessFile() {//复制文件。RandomAccessFile已经被JDK1.4的nio的"内存映射文件(memory-mapped files)"给取代了。        try (RandomAccessFile r = new RandomAccessFile("c://1.wmv", "r");             RandomAccessFile w = new RandomAccessFile("d://2.wmv", "rw")) {            byte[] buffer = new byte[1024 * 1024];            int n = 0;            while ((n = r.read(buffer)) != -1) {                w.write(buffer, 0, n);            }        } catch (Exception e) {            e.printStackTrace();        }    }//    @Test    public void divideRandomAccessFile(){//将1.txt分割为多个        try(RandomAccessFile r=new RandomAccessFile("D:\\file\\1.txt","r")){            byte[] buffer=new byte[2];            int n=0;            int i=1;            while((n=r.read(buffer))!=-1){                RandomAccessFile w=new RandomAccessFile("D:\\file\\1_"+(i++)+".txt","rw");                w.write(buffer,0,n);            }        }catch (IOException e) {            e.printStackTrace();        }    }    @Test    public void mergeFile(){//将多个1_?.txt文件合并为一个1.txt文件        File file=null;        try(RandomAccessFile w=new RandomAccessFile("D:\\file\\1.txt","rw")){            int i=1;            while((file=new File("D:\\file\\1_"+(i++)+".txt")).exists()){                RandomAccessFile r=new RandomAccessFile(file,"r");                copyTo(r,w);            }        }catch(IOException e){e.printStackTrace();}    }    private void copyTo(RandomAccessFile r, RandomAccessFile w) throws IOException {        byte[] buffer=new byte[8];        int n=0;        while((n=r.read(buffer))!=-1){            w.write(buffer,0,n);        }    }}