javaIO读和写和创建文件夹的基础简单操作

package com.zuoye16;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class FileUtil {
public static final String PATH=System.getProperty("user.dir");
public void cj(String path) {

File file=new File(PATH+path);
int index=path.indexOf(".");
if(index==-1) {
if(!file.exists()) {
file.mkdirs();
}
}else {
int index2=path.lastIndexOf("/");
String string=path.substring(0, index2);
if(!file.exists()) {
File file2=new File(PATH+string);
file2.mkdirs();
}

}
try {
file.createNewFile();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}

//读和写的初始化
FileReader fileReader=null;
FileWriter fileWriter=null;
try {

//读和写的初始化
fileReader=new FileReader(file);
fileUtil.cj("/src/com/lanou/day18/Text.txt");
fileWriter=new FileWriter(fileName);
//将读出来的数据写入
int lenght=0;
char[] context=new char[1024];
while((lenght=fileReader.read(context))!=-1) {
fileWriter.write(context,0,lenght);

}

//完成后刷新
fileWriter.flush();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {
if(fileWriter!=null) {
try {

//关闭写入流
fileWriter.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

}

}