001 /* 002 * Licensed under the Apache License, Version 2.0 (the "License"); 003 * you may not use this file except in compliance with the License. 004 * You may obtain a copy of the License at 005 * 006 * http://www.apache.org/licenses/LICENSE-2.0 007 * 008 * Unless required by applicable law or agreed to in writing, software 009 * distributed under the License is distributed on an "AS IS" BASIS, 010 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 011 * See the License for the specific language governing permissions and 012 * limitations under the License. 013 */ 014 package org.apache.commons.classscan.builtin; 015 016 import java.util.Iterator; 017 import java.util.NoSuchElementException; 018 019 import org.apache.commons.classscan.ClassFile; 020 021 public abstract class ClassFileIterator implements Iterator<ClassFile> { 022 023 private ClassFile prefetch; 024 025 abstract ClassFile getNext(); 026 027 @Override 028 public boolean hasNext() { 029 if(prefetch==null) { 030 prefetch= getNext(); 031 } 032 return prefetch!=null; 033 } 034 035 @Override 036 public ClassFile next() { 037 if(prefetch!=null) { 038 ClassFile rc= prefetch; 039 prefetch= null; 040 return rc; 041 } 042 ClassFile rc= getNext(); 043 if(rc==null) { 044 throw new NoSuchElementException(); 045 } 046 return rc; 047 } 048 049 @Override 050 public void remove() { 051 throw new UnsupportedOperationException(); 052 } 053 }