Java tutorial
/* Copyright 2013 Future TV, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package tv.icntv.grade.film.utils; import com.google.common.io.Closeables; import com.google.common.io.Files; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.*; import org.apache.hadoop.io.Closeable; import org.apache.hadoop.io.SequenceFile; import org.apache.hadoop.io.Text; import org.apache.mahout.common.HadoopUtil; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; /** * Created with IntelliJ IDEA. * User: xiaowu lei * Date: 13-12-5 * Time: ?9:04 */ public class HadoopUtils { private static Configuration configuration = new Configuration(); public static boolean isExist(Path path) throws IOException { FileSystem fileSystem = null; try { fileSystem = FileSystem.get(configuration); return fileSystem.exists(path); } catch (Exception e) { return false; } finally { if (null != fileSystem) { fileSystem.close(); } } } public static void deleteIfExist(String path) throws IOException { FileSystem fileSystem = null; try { fileSystem = FileSystem.get(configuration); Path p = new Path(path); if (fileSystem.exists(p)) { fileSystem.delete(p, true); } } catch (IOException e) { e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates. } finally { if (null != fileSystem) { fileSystem.close(); } } } public static boolean isExist(Path... paths) throws IOException { if (null == paths || paths.length == 0) { return false; } for (Path path : paths) { if (!isExist(path)) { return false; } } return true; } public static void save(Path path, Long size) throws IOException { FileSystem fileSystem = null; FSDataOutputStream out = null; try { fileSystem = FileSystem.get(configuration); if (fileSystem.exists(path)) { fileSystem.delete(path); out = fileSystem.create(path); out.writeLong(size); out.flush(); } } catch (Exception e) { return; } finally { Closeables.close(out, true); if (null != fileSystem) { fileSystem.close(); } } } public static long count(Path path, PathFilter filter) throws Exception { FileSystem fileSystem = null; try { fileSystem = FileSystem.get(configuration); FileStatus[] fs = fileSystem.listStatus(path, filter); long count = 0; for (FileStatus f : fs) { SequenceFile.Reader frequentPatternsReader = new SequenceFile.Reader(fileSystem, f.getPath(), configuration); Text key = new Text(); while (frequentPatternsReader.next(key)) { count++; } frequentPatternsReader.close(); } return count; } catch (Exception e) { throw e; } finally { // Closeables.close(br,true); if (null != fileSystem) { fileSystem.close(); } } } public static void main(String[] args) throws Exception { Configuration configuration = new Configuration(); // deleteIfExist("/icntv/grade/db/2013-12-12/chinacache_table_1"); // long c= count(new Path("/icntv/grade/correlate-fp-growth/2013-12-10/frequentpatterns"),new PathFilter() { // @Override // public boolean accept(Path path) { // // return path.getName().matches("part-r-\\d*"); // } // }); // System.out.println(c); // String line="shut"; // System.out.println(line.matches("\\d*")); FileSystem fileSystem = FileSystem.get(configuration); BufferedReader b = new BufferedReader(new InputStreamReader( fileSystem.open(new Path("/icntv/grade/num/middle/2013-12-18/part-r-00000")))); String line = null; while (null != (line = b.readLine())) { System.out.println(line.split("\t").length + " --- " + line); } b.close(); // FileStatus[] fs=fileSystem.listStatus(new Path("/icntv/grade/score/base/2013-12-09"),new PathFilter() { // @Override // public boolean accept(Path path) { // return path.getName().matches("part-r-\\d*"); // } // }); // BufferedReader br =null; // String line="shoutcastsource"; // for(FileStatus f:fs){ //// fileSystem.open(f.getPath()) // br = new BufferedReader( new InputStreamReader(fileSystem.open(f.getPath()))); // String l=null; // while (null!=(l=br.readLine())){ // if(l.contains(line)){ // System.out.println(l); // } // } // } // Closeables.close(br,true); // if(null != fileSystem){ // fileSystem.close(); // } } }