file 同时 读写删除

1，同时可以读写，写写，但读写时不能删除。运行下面代码并通过输出验证

package test;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
import java.nio.file.Files;

public class TestFile {
    
    public static void main( String[] args ) {
        final TestFile testFile = new TestFile();
        new Thread(new Runnable() {
            @Override
            public void run() {
                for(int i = 0; i< 10; i++){
                    try {
                        Thread.sleep( 100 );
                    }
                    catch ( InterruptedException e ) {
                        e.printStackTrace();
                    }
                    testFile.write( Thread.currentThread() + "- line - "+i +"\n");
                }
            }
        }).start();
        new Thread(new Runnable() {
            @Override
            public void run() {
                for(int i = 0; i< 10; i++){
                    try {
                        Thread.sleep( 100 );
                    }
                    catch ( InterruptedException e ) {
                        e.printStackTrace();
                    }
                    testFile.read();
                }
            }
        }).start();
        new Thread(new Runnable() {
            @Override
            public void run() {
                for(int i = 0; i< 10; i++){
                    try {
                        Thread.sleep( 100 );
                    }
                    catch ( InterruptedException e ) {
                        e.printStackTrace();
                    }
                    testFile.write( Thread.currentThread() + "- line - "+i +"\n");
                }
            }
        }).start();
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    Thread.sleep( 500 );
                    Files.delete( new File( "d:/a.txt" ).toPath() );
                }
                catch ( Exception e ) {
                    //java.nio.file.FileSystemException: d:\a.txt: The process cannot access the file because it is being used by another process.
                    e.printStackTrace();
                }
            }
        }).start();
    }
    
    private void write(String str){
        try {
            FileOutputStream fos = new FileOutputStream( "d:/a.txt",true );
            fos.write( str.getBytes() );
        }
        catch ( Exception e ) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    private void read(){
        try {
            FileInputStream fis = new FileInputStream( "d:/a.txt" );
            BufferedReader br = new BufferedReader( new InputStreamReader( fis ) );
            String str = br.readLine();
            while(str != null){
                System.out.println(str);
                str = br.readLine();
            }
        }
        catch ( Exception e ) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
}

 2，必须流关闭才能删除，rename（这个很特殊，win与linux下表现不同，getName()也很神奇）。外部流和内部类close效果一样。因为是委托代理组合，内部类的close

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;

public class TestFile {

    public static void main( String[] args ) {
        final TestFile testFile = new TestFile();
        testFile.write( "test - line -1. \n" );
    }

    private void write( String str ) {
        try {
            File file = new File( "d:/a.txt" );
            FileOutputStream fos = new FileOutputStream( file, true );
            BufferedWriter bw = new BufferedWriter(new OutputStreamWriter( fos ));
            bw.write( str );
            System.out.println(file.renameTo( new File( "d:/a1.txt" ) ));
            System.out.println(file.getName()+" delete result = " + file.delete());
            bw.close();
            fos.close();
            System.out.println(file.renameTo( new File( "d:/a1.txt" ) ));
            System.out.println(file.getName()+" delete result = " + file.delete());
        }
        catch ( Exception e ) {
            e.printStackTrace();
        }
    }
}