Lucene index maintenance

1. Modify Index

　　The index is updated to delete the add, it is recommended to use this method to update the needs, and to ensure the implementation of existing update the index, you can check out, update records to determine the existence of an update operation.
　　If you update the index of the target document object does not exist, do add.

/ ** 
     * Modify the index database 
     * / 
    @Test 
    public  void testUpdateIndex () throws IOException { 

        // create analyzer (tokenizer) StandardAnalyzer standard word breaker, the English word good effect, Chinese is the word word 
        Analyzer Analyzer = new new StandardAnalyzer ( );
         // create IndexWriterConfig class configuration information, specify word segmentation word used 
        IndexWriterConfig config = new new IndexWriterConfig (Analyzer);
         // create the Directory object, the statement index database storage location 
        Directory dir = FSDirectory.open (Paths.get ( " D : \\ Lucene " ));
         // create IndexWriter writing object, config initialize the object location and use of specified written 
        IndexWriter IndexWriter = new newIndexWriter (dir, config); 

        // need to change the contents of 
        the Document the Document = new new the Document (); 

        // create a domain object, and the object in the document 
        document.add ( new new StringField ( "the above mentioned id", "100 000 003 140" , TextField. Store.YES)); 
        document.add ( new new TextField ( "name", "Vivo" , TextField.Store.YES)); 

        // perform the update, will all eligible Document delete, add it again. 
        indexWriter.updateDocument ( new new Term ( "ID", "100 000 003 140" ), Document);
         // release resources 
        indexWriter.close (); 
    }

2. Delete Index

/ ** 
 * Remove index database 
 * / 
@Test 
public  void testDeleteIndex () throws IOException { 

    // create analyzer (tokenizer) StandardAnalyzer standard word breaker, the English word good effect, Chinese is the word word 
    Analyzer Analyzer = new new StandardAnalyzer ( );
     // create IndexWriterConfig class configuration information, specify word segmentation word used 
    IndexWriterConfig config = new new IndexWriterConfig (Analyzer);
     // create the Directory object, the statement index database storage location 
    Directory dir = FSDirectory.open (Paths.get ( " D : \\ Lucene " ));
     // create IndexWriter writing object, config initialize the object location and use of specified written 
    IndexWriter IndexWriter = new new IndexWriter (dir, config); 

    //According Term delete the index database
     // indexWriter.deleteDocuments (new new Term ( "the above mentioned id", "100 000 003 140"));
     // delete all indexes (caution) 
    indexWriter.deleteAll (); 

    // release resources 
    indexWriter.close (); 
}