《Lucene实战(第2版)》 配书代码的下载地址点此,解压后得到lia2e目录,编译运行方法有两种:
最基础的Ant编译:
点击右边的加号载入lia2e下的build.xml脚本,接着在列表里双击某单元对应的程序就行了:
通过IDEA Configuration编译运行:
新建一个控制台配置,选择主类:
编译运行报错:
java: 找不到符号
符号: 方法 next()
位置: 类型为org.apache.lucene.analysis.TokenStream的变量 ts
这是因为lia/analysis/nutch/NutchExample.java需要使用Lucene 2.4.0,但是配书代码用的是3.0:
<!– Nutch uses Lucene 2.4.0, but the rest of the sources use 3.0.0,
so we set up a separate compile target & classpath –>
解决方案是注释掉NutchExample,在第四章要用到的话再改回了来用Ant编译。
接下来编译成功,运行出错:
Exception in thread "main" java.lang.IllegalArgumentException: Usage: java lia.meetlucene.Indexer <index dir> <data dir>
at lia.meetlucene.Indexer.main(Indexer.java:41)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
少了两个参数而已,改成:
package lia.meetlucene; /** * Copyright Manning Publications Co. * * 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 lan */ import org.apache.lucene.index.IndexWriter; import org.apache.lucene.analysis.standard.StandardAnalyzer; import org.apache.lucene.document.Document; import org.apache.lucene.document.Field; import org.apache.lucene.store.FSDirectory; import org.apache.lucene.store.Directory; import org.apache.lucene.util.Version; import java.io.File; import java.io.FileFilter; import java.io.IOException; import java.io.FileReader; // From chapter 1 /** * This code was originally written for * Erik's Lucene intro java.net article */ public class Indexer { public static void main(String[] args) throws Exception { args = new String[2]; args[0] = "indexes/MeetLucene"; args[1] = "src/lia/meetlucene/data"; if (args.length != 2) { throw new IllegalArgumentException("Usage: java " + Indexer.class.getName() + " <index dir> <data dir>"); } String indexDir = args[0]; //1 String dataDir = args[1]; //2 long start = System.currentTimeMillis(); Indexer indexer = new Indexer(indexDir); int numIndexed; try { numIndexed = indexer.index(dataDir, new TextFilesFilter()); } finally { indexer.close(); } long end = System.currentTimeMillis(); System.out.println("Indexing " + numIndexed + " files took " + (end - start) + " milliseconds"); } private IndexWriter writer; public Indexer(String indexDir) throws IOException { Directory dir = FSDirectory.open(new File(indexDir)); writer = new IndexWriter(dir, //3 new StandardAnalyzer( //3 Version.LUCENE_30),//3 true, //3 IndexWriter.MaxFieldLength.UNLIMITED); //3 } public void close() throws IOException { writer.close(); //4 } public int index(String dataDir, FileFilter filter) throws Exception { File[] files = new File(dataDir).listFiles(); for (File f: files) { if (!f.isDirectory() && !f.isHidden() && f.exists() && f.canRead() && (filter == null || filter.accept(f))) { indexFile(f); } } return writer.numDocs(); //5 } private static class TextFilesFilter implements FileFilter { public boolean accept(File path) { return path.getName().toLowerCase() //6 .endsWith(".txt"); //6 } } protected Document getDocument(File f) throws Exception { Document doc = new Document(); doc.add(new Field("contents", new FileReader(f))); //7 doc.add(new Field("filename", f.getName(), //8 Field.Store.YES, Field.Index.NOT_ANALYZED));//8 doc.add(new Field("fullpath", f.getCanonicalPath(), //9 Field.Store.YES, Field.Index.NOT_ANALYZED));//9 return doc; } private void indexFile(File f) throws Exception { System.out.println("Indexing " + f.getCanonicalPath()); Document doc = getDocument(f); writer.addDocument(doc); //10 } } /* #1 Create index in this directory #2 Index *.txt files from this directory #3 Create Lucene IndexWriter #4 Close IndexWriter #5 Return number of documents indexed #6 Index .txt files only, using FileFilter #7 Index file content #8 Index file name #9 Index file full path #10 Add document to Lucene index */
运行成功:
Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\apache1.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\apache1.1.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\apache2.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\cpl1.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\epl1.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\freebsd.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\gpl1.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\gpl2.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\gpl3.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\lgpl2.1.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\lgpl3.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\lpgl2.0.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\mit.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\mozilla1.1.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\mozilla_eula_firefox3.txt Indexing D:\JavaProjects\lia2e\src\lia\meetlucene\data\mozilla_eula_thunderbird2.txt Indexing 16 files took 369 milliseconds Process finished with exit code 0
你好!
在添加了您说的两个参数后,会报错,不知道是什么原因
Exception in thread “main” java.lang.NullPointerException
at lia.meetlucene.Indexer.index(Indexer.java:85)
at lia.meetlucene.Indexer.main(Indexer.java:55)
应该是我的参数的路径不对 我在run configuration–Argument中,将第二个参数args[1]的路径设置为Project Explorer中lia.meetlucene.data的路径,就运行成功了。跟着大牛的脚步亦步亦趋。
一直想买这本书来着,可是书太多也没时间看~