| /* |
| * Copyright 1999-2004 The Apache Software Foundation |
| * |
| * 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 language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.tomcat.util.collections; |
| |
| import java.util.Enumeration; |
| |
| /** Enumerate the distinct header names. |
| Each nextElement() is O(n) ( a comparation is |
| done with all previous elements ). |
| |
| This is less frequesnt than add() - |
| we want to keep add O(1). |
| */ |
| public final class MultiMapNamesEnumeration implements Enumeration { |
| int pos; |
| int size; |
| String next; |
| MultiMap headers; |
| |
| // toString and unique options are not implemented - |
| // we allways to toString and unique. |
| |
| /** Create a new multi-map enumeration. |
| * @param headers the collection to enumerate |
| * @param toString convert each name to string |
| * @param unique return only unique names |
| */ |
| MultiMapNamesEnumeration(MultiMap headers, boolean toString, |
| boolean unique) { |
| this.headers=headers; |
| pos=0; |
| size = headers.size(); |
| findNext(); |
| } |
| |
| private void findNext() { |
| next=null; |
| for( ; pos< size; pos++ ) { |
| next=headers.getName( pos ).toString(); |
| for( int j=0; j<pos ; j++ ) { |
| if( headers.getName( j ).equalsIgnoreCase( next )) { |
| // duplicate. |
| next=null; |
| break; |
| } |
| } |
| if( next!=null ) { |
| // it's not a duplicate |
| break; |
| } |
| } |
| // next time findNext is called it will try the |
| // next element |
| pos++; |
| } |
| |
| public boolean hasMoreElements() { |
| return next!=null; |
| } |
| |
| public Object nextElement() { |
| String current=next; |
| findNext(); |
| return current; |
| } |
| } |