java io 练习 - 黑马程序员技术交流社区

/*
字符串-》文件 show1();
文件-》控制台 show2();
1、明确源和目的源：Reader InputStream目的：Writer OutputStream
2、明确是否纯文本数据源：Reader 目的：Writer
3、明确具体设备源文件File 目的控制台 System.out
FileReader =new FileReader(fileName);
OutputStream os=System.out;
4、明确是否需要额外功能，转换，高效
转换：OutputStreamWriter osw=new OutputStreamWriter(new OutputStream(System.out));
高效;BufferedReader bfr=new BufferedReader(new FileReader(filename));
BufferedWriter bfw=new BufferedWriter(new OutputStreamWriter(System.out));
文件-》文件 show3();
1、明确源和目的源:Reader inpuStream 目的：Writer OutputStream
2、明确数据是否纯文本源：Reader 目的：writer
3、明确具体设备源硬盘 file 目的file
FileReader fr=new FileReader(filename);
FileWriter fw=new FileWriter(filename);
4、是否需要额外功能
转换，不需要
高效需要
BufferedReader bfr=new BufferedReader(new FileReader(fileName));
BufferedWriter bfw=new BufferedWriter(new FileWriter(fileName));
键盘-》文件 show4();
1、明确源和目的源：Reader InputStream 目的：Writer OutputStream
2、明确是否纯文本数据源：Reader 目的：writer
3、明确具体设备源键盘 system.in 目的硬盘 File
InputStream in=System.in;
FileWriter fw=new FileWriter(filename);
4、明确是否需要额外功能
转换：InputStreamReader inr=new InputStreamReader(System.in);
高效：BufferedReader bfr=new BufferedReader(new InputStreamReader(System.in));
BufferedWriter bfw=new BufferedWriter(new FileWriter(filename));
键盘-》控制台 show(5);
1、明确源和目的源：Reader InputStream 目的：Writer OutputStream
2、明确是否纯文本数据源：Reader 目的：writer
3、明确具体设备源键盘 System.in 目的：控制台 System.out
InputStream in=System.in;
OutputStream out=System.out;
4、明确是否需要额外功能
转换：InputStreamReader inr=new InputStreamReader(System.in);
OutputStreamWriter outw=new OutputStreamWriter(System.out);
高效：
BufferedReader bfr=new BufferedReader(new InputStreamReader(System.in));
BufferedWriter bfw=new BufferedWriter(new OutputStreamWriter(System.out));
*/
import java.io.FileReader;
import java.io.FileWriter;
import java.io.OutputStream;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.io.InputStreamReader;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
public class IODemo
{
private static final String LINE_SEPARATOR=System.getProperty("line.separator");
public static void main(String[] args){
show5();
}
//////////////////////////////////////////////////////
public static void show5(){
BufferedReader bfr=null;
BufferedWriter bfw=null;
try
{
bfr=new BufferedReader(new InputStreamReader(System.in));
bfw=new BufferedWriter(new OutputStreamWriter(System.out));
String s=bfr.readLine();
while(!s.equals("over")){
bfw.write(s+"----");
bfw.newLine();
bfw.flush();
s=bfr.readLine();
}
}
catch (IOException e)
{
e.printStackTrace();
}finally{
if(bfr!=null){
try
{
bfr.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
if(bfw!=null){
try
{
bfw.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
}
//////////////////////////////////////////////////////
public static void show4(){
BufferedReader bfr=null;
BufferedWriter bfw=null;
try
{
bfr=new BufferedReader(new InputStreamReader(System.in));
bfw=new BufferedWriter(new FileWriter("seven.txt"));
String s=null;
while((s=bfr.readLine())!=null){
bfw.write(s);
bfw.newLine();
bfw.flush();
if(s.equals("over"))
System.exit(0);
}
}
catch (IOException e)
{
e.printStackTrace();
}finally{
if(bfr!=null){
try
{
bfr.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
if(bfw!=null){
try
{
bfw.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
}
//////////////////////////////////////////////////////
public static void show3(){
BufferedReader bfr=null;
BufferedWriter bfw=null;
try
{
bfr=new BufferedReader(new FileReader("IODemo.java"));
bfw=new BufferedWriter(new FileWriter("IODemo_copy.java"));
String buf=null;
while((buf=bfr.readLine())!=null){
bfw.write(buf);
bfw.newLine();
bfw.flush();
}
}
catch (IOException e)
{
e.printStackTrace();
}finally{
if(bfr!=null){
try
{
bfr.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
if(bfw!=null){
try
{
bfw.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
}
//////////////////////////////////////////////////////
public static void show2(){
BufferedReader bfr=null;
BufferedWriter bfw=null;
try
{
bfr=new BufferedReader(new FileReader("IODemo.java"));
bfw=new BufferedWriter(new OutputStreamWriter(System.out));
char[] ch=new char[1024];
String s=null;
while((s=bfr.readLine())!=null){
System.out.println(s);
bfw.write(s);
bfw.newLine();
bfw.flush();
}
}
catch (IOException e)
{
e.printStackTrace();
}finally{
if(bfr!=null){
try
{
bfr.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
if(bfw!=null){
try
{
bfw.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
}
//////////////////////////////////////////////////////
public static void show1(){
BufferedWriter bfw=null;
try
{
bfw=new BufferedWriter(new FileWriter("IODemo.java",true));
bfw.write("seven,1094578647");
bfw.newLine();
bfw.write("seven,1094578647");
bfw.flush();
}
catch (IOException e)
{
e.printStackTrace();
}finally{
if(bfw!=null){
try
{
bfw.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
}
}

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