org.simpleframework.xml.transform.DefaultMatcher Maven / Gradle / Ivy
/*
* DefaultMatcher.java May 2007
*
* Copyright (C) 2007, Niall Gallagher
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307 USA
*/
package org.simpleframework.xml.transform;
/**
* The DefaultMatcher is a delegation object that uses
* several matcher implementations to correctly resolve both the
* stock Transform implementations and implementations
* that have been overridden by the user with a custom matcher. This
* will perform the resolution of the transform using the specified
* matcher, if this results in no transform then this will look for
* a transform within the collection of implementations.
*
* @author Niall Gallagher
*
* @see org.simpleframework.xml.transform.Transformer
*/
class DefaultMatcher implements Matcher {
/**
* Matcher used to resolve stock transforms for primitive types.
*/
private Matcher primitive;
/**
* Matcher used to resolve user specified transform overrides.
*/
private Matcher matcher;
/**
* Matcher used to resolve all the core Java object transforms.
*/
private Matcher stock;
/**
* Matcher used to resolve transforms for array type objects.
*/
private Matcher array;
/**
* Constructor for the DefaultMatcher object. This
* performs resolution of Transform implementations
* using the specified matcher. If that matcher fails to resolve
* a suitable transform then the stock implementations are used.
*
* @param matcher this is the user specified matcher object
*/
public DefaultMatcher(Matcher matcher) {
this.primitive = new PrimitiveMatcher();
this.stock = new PackageMatcher();
this.array = new ArrayMatcher(this);
this.matcher = matcher;
}
/**
* This is used to match a Transform for the given
* type. If a transform cannot be resolved this this will throw an
* exception to indicate that resolution of a transform failed. A
* transform is resolved by first searching for a transform within
* the user specified matcher then searching the stock transforms.
*
* @param type this is the type to resolve a transform object for
*
* @return this returns a transform used to transform the type
*/
public Transform match(Class type) throws Exception {
Transform value = matcher.match(type);
if(value != null) {
return value;
}
return matchType(type);
}
/**
* This is used to match a Transform for the given
* type. If a transform cannot be resolved this this will throw an
* exception to indicate that resolution of a transform failed. A
* transform is resolved by first searching for a transform within
* the user specified matcher then searching the stock transforms.
*
* @param type this is the type to resolve a transform object for
*
* @return this returns a transform used to transform the type
*/
private Transform matchType(Class type) throws Exception {
if(type.isArray()) {
return array.match(type);
}
if(type.isPrimitive()) {
return primitive.match(type);
}
return stock.match(type);
}
}