package ioStudy;

 import java.io.File;

 import java.io.FileInputStream;

 import java.io.FileNotFoundException;

 import java.io.IOException;

 import java.io.InputStream;

 /*

 1.创建源

 2.选择流

 3.操作

 4.释放资源

 */

 public class IOstudy2 {

     public static void main(String[] args) {

         File file = new File("test.txt");    //创建源

         InputStream is = null;

         try {

             is = new FileInputStream(file);     //  选择流

             int temp;

             while ((temp = is.read()) != -1) {      //一次读一个字节  如果包含中文可能会出现乱码  考虑使用字符流

                 System.out.print((char) temp);    //操作

             }

         } catch (FileNotFoundException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         } catch (IOException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         }finally {

             if(is!=null) {

                 try {

                     is.close();        //释放资源

                 } catch (IOException e) {

                     // TODO Auto-generated catch block

                     e.printStackTrace();

                 }

             }

         }

     }

 }

 package ioStudy;

 import java.io.File;

 import java.io.FileNotFoundException;

 import java.io.FileOutputStream;

 import java.io.IOException;

 import java.io.OutputStream;

 /*

 1.创建源

 2.选择流

 3.操作

 4.释放资源

 */

 public class IOstudy4 {

     public static void main(String[] args) {

         File file = new File("output.txt"); // 不存在会自动创建

         OutputStream os = null;

         try {

             os = new FileOutputStream(file,true);  //开启向后追加  不然每次都删掉原来的 再写  默认的是false

             String temp = "hello world!\r\n";

             byte[] b = temp.getBytes();

             os.write(b, 0, b.length);

             os.flush();   //刷新内存

         } catch (FileNotFoundException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         } catch (IOException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         } finally {

             if (os != null) {

                 try {

                     os.close();

                 } catch (IOException e) {

                     // TODO Auto-generated catch block

                     e.printStackTrace();

                 }

             }

         }

     }

 }

 package ioStudy;

 import java.io.File;

 import java.io.FileInputStream;

 import java.io.FileNotFoundException;

 import java.io.FileOutputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.OutputStream;

 /*

 1.创建源

 2.选择流

 3.操作

 4.释放资源

 */

 public class Copy {

     public static void main(String[] args) {

         copy("test.txt","testcopy.txt");

     }

     public static void copy(String source, String destination) {

         File src = new File(source);

         File dest = new File(destination);

         InputStream is = null;

         OutputStream os = null;

         try {

             is = new FileInputStream(src);

             os = new FileOutputStream(dest);

             byte[] buffer = new byte[1034];

             int len;

             while ((len = is.read(buffer)) != -1) {

                 os.write(buffer, 0, len);

                 os.flush();

             }

         } catch (FileNotFoundException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         } catch (IOException e) {

             // TODO Auto-generated catch block

             e.printStackTrace();

         } finally {

             // 流关闭的原则 先打开的后关闭

             if (os != null) {

                 try {

                     os.close();

                 } catch (IOException e) {

                     // TODO Auto-generated catch block

                     e.printStackTrace();

                 }

             }

             if (is != null) {

                 try {

                     is.close();

                 } catch (IOException e) {

                     // TODO Auto-generated catch block

                     e.printStackTrace();

                 }

             }

         }

     }

 }