java文件读写

最新推荐文章于 2023-04-06 22:36:37 发布

原创最新推荐文章于 2023-04-06 22:36:37 发布 · 959 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#java #string #exception #byte #interface #class

java笔记专栏收录该内容

14 篇文章

订阅专栏

//接口类IFile.java

package Demo;

public interface IFile {
public String ReadFile(String fileName);
public void WriteFile(String fileName,String str);
}

//MyFileByteImpl.java字节流读写文件

package Demo;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;

public class MyFileByteImpl implements IFile{

public String ReadFile(String fileName) {
  String str="";
  try {
   byte[] buf=new byte[4];
   FileInputStream fi=new FileInputStream(fileName);
   int b=fi.read(buf);
   while(b!=-1){
   for(int i=0;i<b;i++){
    str+=(char)buf[i];
   }
   b=fi.read(buf);
   }
   fi.close();
  } catch (Exception e) {

   System.out.println(e);
  }
  return str;
}

public void WriteFile(String fileName, String str) {
  try {
   FileOutputStream fo=new FileOutputStream(fileName);
   byte buf[]=str.getBytes();
   fo.write(buf);
   fo.close();
  } catch (Exception e) {
   System.out.println("demo.MyFilterInpuStreamImpl.WriteFile:"+e);
  }

}

}
//myFileCharImpl.java字符流处理文件

package Demo;
import java.io.*;
import java.io.File;
public class MyFileCharImpl implements IFile{

public String ReadFile(String fileName) {
  String str="";
  try {

   FileReader fr=new FileReader(fileName);
   char[] buf=new char[4];
   int b=fr.read(buf);
   while(b!=-1){
    for(int i=0;i<b;i++){
     str+=buf[i];
    }
    b=fr.read(buf);
   }
  } catch ( Exception e) {
   System.out.println(e);
  }

  return str;
}

public void WriteFile(String fileName, String str)
{
  try{
  File myFile=new File(fileName);
  myFile.createNewFile();
  FileWriter filewriter=new FileWriter(myFile,true);
  filewriter.write(str);
  filewriter.close();
  }
  catch (Exception e)
  {
   System.out.println(e);
  }
}
}