1、源码
import org.apache.hadoop.fs.FsUrlStreamHandlerFactory; import org.apache.hadoop.io.IOUtils; import java.io.InputStream; import java.net.URL; /** * Example 3.1 */ public class URLCat { static { URL.setURLStreamHandlerFactory(new FsUrlStreamHandlerFactory()); } public static void main(String[] args) throws Exception { InputStream in = null; try { in = new URL(args[0]).openStream(); IOUtils.copyBytes(in, System.out, 4096, false); } finally { IOUtils.closeStream(in); } } }
package cn.kissoft.hadoop.week04; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IOUtils; import java.io.InputStream; import java.net.URI; /** * Example 3.2 */ public class Homework1 { public static void main(String[] args) throws Exception { String uri = args[0]; Configuration conf = new Configuration(); FileSystem fs = FileSystem.get(URI.create(uri), conf); InputStream in = null; try { in = fs.open(new Path(uri)); IOUtils.copyBytes(in, System.out, 4096, false); } finally { IOUtils.closeStream(in); } } }
2、.class的运行方式
注意:本示例中URLCat类在default package中,如果有包,那类名前面还是要加上包。
3、.jar的运行方式
HDFS API的Helloworld
时间: 2024-11-05 11:33:32