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  • java阅读器hdfs单纯demo

    周围环境:eclipse + eclipse hadoop插入。 hadoop + rhel6.4

    package test;
    
    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; 
    import org.apache.hadoop.fs.FSDataInputStream;
    import org.apache.hadoop.fs.FSDataOutputStream;;
    
    public class Test {
    	
    	
    	public void WriteFile(String hdfs) throws IOException {
    		Configuration conf = new Configuration();
    		FileSystem fs = FileSystem.get(URI.create(hdfs),conf);
    		FSDataOutputStream hdfsOutStream = fs.create(new Path(hdfs));
    		hdfsOutStream.writeChars("hello");
    		hdfsOutStream.close();
    		fs.close();		
    	}
    	
    	public void ReadFile(String hdfs) throws IOException {
    		Configuration conf = new Configuration();
    		FileSystem fs = FileSystem.get(URI.create(hdfs),conf);
    		FSDataInputStream hdfsInStream = fs.open(new Path(hdfs));
    		
    		byte[] ioBuffer = new byte[1024];
    		int readLen = hdfsInStream.read(ioBuffer);
    		while(readLen!=-1)
    		{
    			System.out.write(ioBuffer, 0, readLen);
    			readLen = hdfsInStream.read(ioBuffer);
    		}
    		hdfsInStream.close();
    		fs.close();	
    	}
    		
    	public static void main(String[] args) throws IOException {		
    		String hdfs = "hdfs://192.168.56.112:9000/test/hello.txt";
    		Test t = new Test();		
    		t.WriteFile(hdfs);
    		t.ReadFile(hdfs);
    	  }
    }
    


     

    版权声明:本文博主原创文章,博客,未经同意不得转载。

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  • 原文地址:https://www.cnblogs.com/mengfanrong/p/4821403.html
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