001package votorola.g.web.wic; // Copyright 2008-2009, 2012, Michael Allan. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Votorola Software"), to deal in the Votorola Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicence, and/or sell copies of the Votorola Software, and to permit persons to whom the Votorola Software is furnished to do so, subject to the following conditions: The preceding copyright notice and this permission notice shall be included in all copies or substantial portions of the Votorola Software. THE VOTOROLA SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE VOTOROLA SOFTWARE OR THE USE OR OTHER DEALINGS IN THE VOTOROLA SOFTWARE. 002 003import org.apache.wicket.model.*; 004import votorola.g.lang.*; 005 006 007/** A model wrapper that enforces a maximum length of character sequences. For use only 008 * with models that hold character sequences. (Otherwise, the associated IConverter 009 * should eagerly enforce its own constraints, at conversion time.) 010 * 011 * @see CharSequence 012 */ 013public final @ThreadSafe class ModelLengthLimiter<S extends CharSequence> 014 extends AbstractWrapModel<S> 015{ 016 017 018 /** Constructs a ModelLengthLimiter, or throws an IllegalArgumentException 019 * if the current value of the wrapped model exceeds the constraint. 020 * 021 * @throws ClassCastException if the current value is neither a CharSequence, nor null 022 * 023 * @see #getWrappedModel() 024 * @see #getMaxLength() 025 */ 026 public ModelLengthLimiter( IModel<S> _wrappedModel, int _maxLength ) throws ClassCastException 027 { 028 wrappedModel = _wrappedModel; 029 maxLength = _maxLength; 030 031 lengthConstrained( wrappedModel.getObject(), maxLength ); 032 } 033 034 035 036 /** The length constraint. 037 */ 038 public final int getMaxLength() { return maxLength; } 039 040 041 private final int maxLength; 042 043 044 // /** Sets the length constraint. 045 // * 046 // * @see #getMaxLength() 047 // */ 048 // public final void setMaxLength( int newMaxLength ) { maxLength = newMaxLength; } 049 050 051 052 /** Ensures that character sequence s does not exceed the specified maximum length. 053 * 054 * @return the same sequence s 055 * @throws IllegalArgumentException if sequence s exceeds maxLength 056 */ 057 public static <S extends CharSequence> S lengthConstrained( final S s, final int maxLength ) 058 { 059 if( s == null || s.length() <= maxLength ) return s; 060 061 throw new IllegalArgumentException( "exceeds " + maxLength + " characters: \"" 062 + s.subSequence(0,16) + "...\"" ); 063 } 064 065 066 067 // - I - M o d e l -------------------------------------------------------------------- 068 069 070 /** Sets the model object; or throws an IllegalArgumentException if the object's 071 * string value is longer than the {@linkplain #getMaxLength maximum length}. 072 * 073 * @throws ClassCastException if the object is neither a CharSequence, nor null 074 */ 075 public @Override void setObject( S o ) throws ClassCastException 076 { 077 wrappedModel.setObject( lengthConstrained( o, maxLength )); 078 } 079 080 081 082 public @Override S getObject() { return wrappedModel.getObject(); } 083 084 085 086 // - I - W r a p - M o d e l ---------------------------------------------------------- 087 088 089 public IModel<S> getWrappedModel() { return wrappedModel; } 090 091 092 private final IModel<S> wrappedModel; 093 094 095 096}