org.simpleframework.xml.core.Collector Maven / Gradle / Ivy
/*
* Collector.java December 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.core;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
/**
* The Collector object is used to store variables for
* a deserialized object. Each variable contains the label and value
* for a field or method. The Composite object uses
* this to store deserialized values before committing them to the
* objects methods and fields.
*
* @author Niall Gallagher
*
* @see org.simpleframework.xml.core.Composite
*/
class Collector implements Criteria {
/**
* This is the registry containing all the variables collected.
*/
private final Registry registry;
/**
* This is the context object used by the serialization process.
*/
private final Context context;
/**
* Constructor for the Collector object. This is
* used to store variables for an objects fields and methods.
* Each variable is stored using the name of the label.
*
* @param context this is the context for the deserialization
*/
public Collector(Context context) {
this.registry = new Registry();
this.context = context;
}
/**
* This is used to get the Variable that represents
* a deserialized object. The variable contains all the meta
* data for the field or method and the value that is to be set
* on the method or field.
*
* @param name this is the name of the variable to be acquired
*
* @return this returns the named variable if it exists
*/
public Variable get(String name) {
return registry.get(name);
}
/**
* This is used to remove the Variable from this
* criteria object. When removed, the variable will no longer be
* used to set the method or field when the commit
* method is invoked.
*
* @param name this is the name of the variable to be removed
*
* @return this returns the named variable if it exists
*/
public Variable remove(String name) {
return registry.remove(name);
}
/**
* This is used to acquire an iterator over the named variables.
* Providing an Iterator allows the criteria to be
* used in a for each loop. This is primarily for convenience.
*
* @return this returns an iterator of all the variable names
*/
public Iterator iterator() {
return registry.iterator();
}
/**
* This is used to create a Variable and set it for
* this criteria. The variable can be retrieved at a later stage
* using the name of the label. This allows for repeat reads as
* the variable can be used to acquire the labels converter.
*
* @param label this is the label used to create the variable
* @param value this is the value of the object to be read
*/
public void set(Label label, Object value) throws Exception {
Variable variable = new Variable(label, value);
if(label != null) {
String name = label.getName(context);
String real = label.getName();
if(!registry.containsKey(name)) {
registry.put(real, variable);
registry.put(name, variable);
}
}
}
/**
* This is used to set the values for the methods and fields of
* the specified object. Invoking this performs the population
* of an object being deserialized. It ensures that each value
* is set after the XML element has been fully read.
*
* @param source this is the object that is to be populated
*/
public void commit(Object source) throws Exception {
Collection set = registry.values();
for(Variable entry : set) {
Contact contact = entry.getContact();
Object value = entry.getValue();
contact.set(source, value);
}
}
/**
* The Registry object is used to store variables
* for the collector. All variables are stored under its name so
* that they can be later retrieved and used to populate the
* object when deserialization of all variables has finished.
*
* @author Niall Gallagher
*/
private class Registry extends HashMap {
/**
* This is used to iterate over the names of the variables
* in the registry. This is primarily used for convenience
* so that the variables can be acquired in a for each loop.
*
* @return an iterator containing the names of the variables
*/
public Iterator iterator() {
return keySet().iterator();
}
}
}