hadoop编程实践 - hdfs编程实现判断文件存在性

Posted 2022-09-28 floakss

package test.hdfs;

import java.io.IOException;
import java.net.URI;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

/*
 *  @authr:Kouch
 *  
 *  功能：变成实现判断hdfs上文件是否存在；
 *  
 *  实现：调用hadoopAPI；
 * 
 */
public class IsExsit     
    
    //main
    public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException 
        //配置类
        Configuration conf=new Configuration();
        
        //模拟路径；
        String url="hdfs://localhost:9000/user/kouch/input";
        
        //文件系统对象
        FileSystem fs=FileSystem.get(URI.create(url), conf);
        
        if(isExsit(fs,url)) 
            System.out.println(url+"存在");
        else 
            System.out.println(url+"不存在");
        
        
    
    
    //判断方式
    public static boolean isExsit(FileSystem fs,String path) 
        boolean is=false;
        try 
            is=fs.exists(new Path(path));
         catch (IllegalArgumentException | IOException e) 
            e.printStackTrace();
        
        return is;