【需求】

雙十一或限時購的商品需要被放在指定區域進行搜索.如果重新建立索引消耗過大,方案:重新定義一個過濾器,然后通過新過濾器制定檢索條件.

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【示例】

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1 /** 2 * 為指定路徑下的文件創建索引 3 * @param filePath 4 */ 5 public void createIndex(String path, String filePath){ 6 IndexWriter writer = null; 7 8 try{ 9 //創建Writer 10 writer = util.getWriter(this.getDirectory(path), this.getConfig()); 11 12 //創建Document 13 Document doc = null; 14 15 //獲取文件列表 16 File list = new File(filePath); 17 18 //創建索引 19 int i = 0; 20 for(File file : list.listFiles()){ 21 doc = new Document(); 22 //建立Id列 23 doc.add(new Field("id",String.valueOf(i++),Field.Store.YES,Field.Index.NOT_ANALYZED)); 24 doc.add(new Field("filename",file.getName(),Field.Store.YES,Field.Index.NOT_ANALYZED_NO_NORMS)); 25 doc.add(new Field("modifydate",Long.toString(file.lastModified()),Field.Store.YES,Field.Index.NOT_ANALYZED_NO_NORMS )); 26 //doc.add(new Field("size",getSize(file.length()),Field.Store.YES,Field.Index.NOT_ANALYZED_NO_NORMS)); 27 28 doc.add(new NumericField("size",Field.Store.YES,true).setLongValue(getSize(file.length()))); 29 doc.add(new NumericField("score2",Field.Store.YES,true).setDoubleValue(Math.random())); 30 doc.add(new Field("path",file.getAbsolutePath(),Field.Store.YES,Field.Index.NOT_ANALYZED_NO_NORMS)); 31 doc.add(new Field("content",new FileReader(file))); 32 33 writer.addDocument(doc); 34 } 35 } 36 catch(Exception ex){ 37 ex.printStackTrace(); 38 } 39 finally{ 40 try { 41 writer.close(); 42 } catch (CorruptIndexException e) { 43 e.printStackTrace(); 44 } catch (IOException e) { 45 e.printStackTrace(); 46 } 47 } 48 }

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1 /** 2 * 限時購商品過濾器 3 * @author Terry 4 * 5 */ 6 public class LimitFilter extends Filter{ 7 //參與限時購商品的Id 8 String[] ids = new String[]{"129"}; 9 10 /** 11 * 獲取文件的集合 12 */ 13 @Override 14 public DocIdSet getDocIdSet(IndexReader reader) throws IOException { 15 //創建DocIdSet 16 //reader.maxDoc() ：獲取最大文件的數量 17 //初始化集合的大小 18 OpenBitSet obs = new OpenBitSet(reader.maxDoc()); 19 20 //初始化OpenbitSet對象 21 //從指定索引開始，到指定索引結束 22 //這里的索引不會出現下標越界的問題，所以不需要使用maxDoc()-1 23 obs.set(0, reader.maxDoc()); 24 25 //遍歷集合中的每一個Id并獲取響應的索引位置 26 //存儲文檔的Id 27 int[] docs = new int[1]; 28 //存儲關鍵字出現的頻率 29 int[] freqs = new int[1]; 30 31 //遍歷預定義的Id的集合 32 for(String id : ids){ 33 //通過id獲取到TermDocs 34 TermDocs td = reader.termDocs(new Term("id",id)); 35 //獲取文檔的ID(id)、freqs(頻率)及count(條目數量) 36 int count = td.read(docs, freqs); 37 System.out.println(id + " | " + count + " | " + docs[0] + " | " + freqs[0]); 38 39 if(count ==1){ 40 //從現有集合中清除當前索引的元素 41 //obs.clear(docs[0]); 42 //obs.set(docs[0]); 43 obs.get(docs[0]); 44 } 45 46 } 47 48 return obs; 49 } 50 }

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1 public class SearchUtil { 2 private String path = "e:\\lucene\\index5"; 3 4 //獲取LuceneUtil實例 5 private LuceneUtil util = LuceneUtil.createInstance(); 6 7 /** 8 * 使用自定義Filter進行過濾 9 * @param key 10 */ 11 public void search(String key){ 12 IndexReader reader =null; 13 IndexSearcher searcher = null; 14 15 try{ 16 //1、創建reader對象 17 reader = util.getReader(FSDirectory.open(new File(path))); 18 19 //2、創建Searcher對象 20 searcher = util.getSeacher(reader); 21 22 //3、創建Query 23 Query query = new TermQuery(new Term("content",key)); 24 25 //4、獲取TopDocs 26 //TopDocs tds =searcher.search(query, 10); 27 //使用自定義過濾器 28 TopDocs tds = searcher.search(query, new LimitFilter(), 10); 29 30 31 //5、獲取ScoreDoc 32 ScoreDoc[] sds = tds.scoreDocs; 33 34 SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); 35 //6、處理數據 36 for(ScoreDoc sd : sds){ 37 Document doc =searcher.doc(sd.doc); 38 39 System.out.println(sd.doc + "、(" + sd.score + ")" + 40 " **【" +doc.get("filename") + " ** " + doc.get("size")+ " ** " + 41 sdf.format(new Date(Long.parseLong(doc.get("modifydate"))))+ " ** " + doc.get("path")+"】"); 42 } 43 } 44 catch(Exception e){ 45 e.printStackTrace(); 46 } 47 finally{ 48 try { 49 searcher.close(); 50 } catch (IOException e) { 51 // TODO Auto-generated catch block 52 e.printStackTrace(); 53 } 54 } 55 } 56 }

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【優化自定義Filter】

1 enum AccessMethod{ 2 ADD, 3 CLEAR 4 } 5 6 public interface AccessList { 7 //獲取域名稱 8 public String getField(); 9 //獲取值列表 10 public String[] getValues(); 11 //獲取方式 12 public AccessMethod getMethod(); 13 } 1 /** 2 * 限時購的列表 3 * @author Terry 4 * 5 */ 6 public class LimitAccessList implements AccessList{ 7 private String field; 8 private AccessMethod method; 9 private String[] values; 10 11 public LimitAccessList(String field, AccessMethod method, String[] values){ 12 this.field = field; 13 this.method = method; 14 this.values = values; 15 } 16 17 @Override 18 public String getField() { 19 return this.field; 20 } 21 22 @Override 23 public String[] getValues() { 24 // TODO Auto-generated method stub 25 return this.values; 26 } 27 28 @Override 29 public AccessMethod getMethod() { 30 // TODO Auto-generated method stub 31 return this.method; 32 } 33 34 } 1 /** 2 * 限時購商品過濾器 3 * @author Terry 4 * 5 */ 6 public class LimitFilter extends Filter{ 7 //參與限時購商品的Id 8 //String[] ids = new String[]{"129"}; 9 private AccessList list = null; 10 11 /** 12 * 構造函數 13 * @param list 14 */ 15 public LimitFilter(AccessList list) { 16 this.list = list; 17 } 18 19 20 21 /** 22 * 獲取文件的集合 23 */ 24 @Override 25 public DocIdSet getDocIdSet(IndexReader reader) throws IOException { 26 //創建DocIdSet 27 //reader.maxDoc() ：獲取最大文件的數量 28 //初始化集合的大小 29 OpenBitSet obs = new OpenBitSet(reader.maxDoc()); 30 31 //初始化OpenbitSet對象 32 //從指定索引開始，到指定索引結束 33 //這里的索引不會出現下標越界的問題，所以不需要使用maxDoc()-1 34 obs.set(0, reader.maxDoc()); 35 36 //遍歷集合中的每一個Id并獲取響應的索引位置 37 //存儲文檔的Id 38 int[] docs = new int[1]; 39 //存儲關鍵字出現的頻率 40 int[] freqs = new int[1]; 41 42 //遍歷預定義的Id的集合 43 for(String id : list.getValues()){ 44 //通過id獲取到TermDocs 45 TermDocs td = reader.termDocs(new Term(list.getField(),id)); 46 //獲取文檔的ID(id)、freqs(頻率)及count(條目數量) 47 int count = td.read(docs, freqs); 48 System.out.println(id + " | " + count + " | " + docs[0] + " | " + freqs[0]); 49 50 if(count ==1){ 51 //從現有集合中清除當前索引的元素 52 if(list.getMethod() == AccessMethod.CLEAR) 53 obs.clear(docs[0]); 54 //obs.set(docs[0]); 55 } 56 57 } 58 59 return obs; 60 } 61 } 1 public class SearchUtil { 2 private String path = "e:\\lucene\\index5"; 3 4 //獲取LuceneUtil實例 5 private LuceneUtil util = LuceneUtil.createInstance(); 6 7 /** 8 * 使用自定義Filter進行過濾 9 * @param key 10 */ 11 public void search(String key){ 12 IndexReader reader =null; 13 IndexSearcher searcher = null; 14 15 try{ 16 //1、創建reader對象 17 reader = util.getReader(FSDirectory.open(new File(path))); 18 19 //2、創建Searcher對象 20 searcher = util.getSeacher(reader); 21 22 //3、創建Query 23 Query query = new TermQuery(new Term("content",key)); 24 25 //4、獲取TopDocs 26 //TopDocs tds =searcher.search(query, 10); 27 //使用自定義過濾器 28 //TopDocs tds = searcher.search(query, new LimitFilter(), 10); 29 AccessList list = new LimitAccessList("id",AccessMethod.ADD, new String[]{"98","100"}); 30 TopDocs tds = searcher.search(query, new LimitFilter(list), 10); 31 32 //5、獲取ScoreDoc 33 ScoreDoc[] sds = tds.scoreDocs; 34 35 SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); 36 //6、處理數據 37 for(ScoreDoc sd : sds){ 38 Document doc =searcher.doc(sd.doc); 39 40 System.out.println(sd.doc + "、(" + sd.score + ")" + 41 " **【" +doc.get("filename") + " ** " + doc.get("size")+ " ** " + 42 sdf.format(new Date(Long.parseLong(doc.get("modifydate"))))+ " ** " + doc.get("path")+"】"); 43 } 44 } 45 catch(Exception e){ 46 e.printStackTrace(); 47 } 48 finally{ 49 try { 50 searcher.close(); 51 } catch (IOException e) { 52 // TODO Auto-generated catch block 53 e.printStackTrace(); 54 } 55 } 56 } 57 }

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轉載于:https://www.cnblogs.com/zhzcode/p/9884081.html

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