import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import org.junit.Test;
public class IODemo {
@Test
public void Output(){
File file = new File("D:"+File.separator+"a"+File.separator+"output.dat");
/*处理文件与目录*/
if(!file.exists()){
//创建目录
File dir = file.getParentFile();
if(!dir.exists()){
dir.mkdirs();
}
//创建新文件
try {
file.createNewFile();
} catch (IOException e) {
System.out.println("创建新文件失败");
}
}
PrintWriter pw = null;
try {
//字节输出流,在原文件后追加
FileOutputStream fos = new FileOutputStream(file,true);
//设定字符集
OutputStreamWriter osw = new OutputStreamWriter(fos,"utf-8");
//缓冲字符输出流
pw = new PrintWriter(osw);
pw.println("呵呵!");
pw.println("哈哈");
pw.println("摩擦");
pw.append("摩擦");
pw.append("摩擦");
pw.append("魔鬼的步伐");
} catch (FileNotFoundException e) {
System.out.println("指定的File没找到!");
} catch (UnsupportedEncodingException e) {
System.out.println("系统不支持的编码!");
} finally{
if(pw != null){
pw.close();
}
}
System.out.println("输出结束");
}
@Test
public void Input(){
File file = new File("D:"+File.separator+"a"+File.separator+"output.dat");
/*处理文件与目录*/
if(!file.exists()){
throw new IllegalArgumentException("目录:"+file+"不存在.");
}
BufferedReader br = null;
try {
//字节输出流,在原文件后追加
FileInputStream fis = new FileInputStream(file);
//设定字符集
InputStreamReader isw = new InputStreamReader(fis,"utf-8");
//缓冲字符输出流
br = new BufferedReader(isw);
StringBuffer sb = new StringBuffer();
String read = null;
while((read=br.readLine()) != null){
sb.append(read+"\n");
}
System.out.println(sb);
} catch (FileNotFoundException e) {
System.out.println("指定的File没找到!");
} catch (UnsupportedEncodingException e) {
System.out.println("系统不支持的编码!");
} catch (IOException e) {
System.out.println("不知道是什么错误");
}finally{
if(br != null){
try {
br.close();
} catch (IOException e) {
System.out.println("输入流关闭异常");
}
}
}
System.out.println("读取结束");
}
}