001/* 002 * BioJava development code 003 * 004 * This code may be freely distributed and modified under the 005 * terms of the GNU Lesser General Public Licence. This should 006 * be distributed with the code. If you do not have a copy, 007 * see: 008 * 009 * http://www.gnu.org/copyleft/lesser.html 010 * 011 * Copyright for this code is held jointly by the individual 012 * authors. These should be listed in @author doc comments. 013 * 014 * For more information on the BioJava project and its aims, 015 * or to join the biojava-l mailing list, visit the home page 016 * at: 017 * 018 * http://www.biojava.org/ 019 * 020 */ 021 022package org.biojava.bio.program.gff; 023 024 025/** 026 * An object that filters a stream of GFF, forwarding some 027 * <span class="type">GFFRecord</span>s to a 028 * listening <span class="type">GFFDocumentHandler</span>, and dropping others. 029 * <p> 030 * The choice to forward or drop is made by a 031 * <span class="type">GFFRecordFilter</span>. 032 * <p> 033 * Unless otherwise stated, all methods forward to the listening handler without 034 * altering the arguments in any way. 035 * 036 * @author Matthew Pocock 037 */ 038public class GFFFilterer implements GFFDocumentHandler { 039 /** 040 * The <span class="type">GFFDocumentHandler</span> that will recieve all 041 * accepted entries. 042 */ 043 private GFFDocumentHandler handler; 044 /** 045 * The <span class="type">GFFRecordFilter</span> that will decide what gets 046 * forwarded. 047 */ 048 private GFFRecordFilter filter; 049 050 /** 051 * Create a new <span class="type">GFFFilterer</span> that will forward 052 * to <span class="arg">handler</span> everything that 053 * <span class="arg">filter</span> accepts. 054 * 055 * @param handler the listening <span class="type">GFFDocumentHandler</span> 056 * @param filter the <span class="type">GFFRecordFilter</span> that decides 057 * what is forwarded to <span class="arg">handler</span> 058 */ 059 public GFFFilterer(GFFDocumentHandler handler, GFFRecordFilter filter) { 060 this.handler = handler; 061 this.filter = filter; 062 } 063 064 public void startDocument(String locator) { 065 handler.startDocument(locator); 066 } 067 068 public void endDocument() { 069 handler.endDocument(); 070 } 071 072 public void commentLine(String comment) { 073 handler.commentLine(comment); 074 } 075 076 /** 077 * Only forward the <span class="type">GFFRecord</span>s that match a filter. 078 */ 079 public void recordLine(GFFRecord record) { 080 if(filter.accept(record)) { 081 handler.recordLine(record); 082 } 083 } 084}