org.simpleframework.xml.core.MethodContact Maven / Gradle / Ivy
/*
* MethodContact.java April 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.lang.annotation.Annotation;
import java.lang.reflect.Method;
/**
* The MethodContact object is acts as a contact that
* can set and get data to and from an object using methods. This
* requires a get method and a set method that share the same class
* type for the return and parameter respectively.
*
* @author Niall Gallagher
*
* @see org.simpleframework.xml.core.MethodScanner
*/
class MethodContact implements Contact {
/**
* This is the label that marks both the set and get methods.
*/
private Annotation label;
/**
* This is the set method which is used to set the value.
*/
private MethodPart set;
/**
* This is the dependent types as taken from the get method.
*/
private Class[] items;
/**
* This is the dependent type as taken from the get method.
*/
private Class item;
/**
* This is the type associated with this point of contact.
*/
private Class type;
/**
* This is the get method which is used to get the value.
*/
private Method get;
/**
* This represents the name of the method for this contact.
*/
private String name;
/**
* Constructor for the MethodContact object. This is
* used to compose a point of contact that makes use of a get and
* set method on a class. The specified methods will be invoked
* during the serialization process to get and set values.
*
* @param get this forms the get method for the object
*/
public MethodContact(MethodPart get) {
this(get, null);
}
/**
* Constructor for the MethodContact object. This is
* used to compose a point of contact that makes use of a get and
* set method on a class. The specified methods will be invoked
* during the serialization process to get and set values.
*
* @param get this forms the get method for the object
* @param set this forms the get method for the object
*/
public MethodContact(MethodPart get, MethodPart set) {
this.label = get.getAnnotation();
this.items = get.getDependents();
this.item = get.getDependent();
this.get = get.getMethod();
this.type = get.getType();
this.name = get.getName();
this.set = set;
}
/**
* This is used to identify annotated methods are fields that
* can not be modified. Such field will require that there is
* a constructor that can have the value injected in to it.
*
* @return this returns true if the field or method is final
*/
public boolean isFinal() {
return set == null;
}
/**
* This is the annotation associated with the point of contact.
* This will be an XML annotation that describes how the contact
* should be serialized and deserialized from the object.
*
* @return this provides the annotation associated with this
*/
public Annotation getAnnotation() {
return label;
}
/**
* This is the annotation associated with the point of contact.
* This will be an XML annotation that describes how the contact
* should be serializaed and deserialized from the object.
*
* @param type this is the type of the annotation to acquire
*
* @return this provides the annotation associated with this
*/
public T getAnnotation(Class type) {
T label = get.getAnnotation(type);
if(label == null && set != null) {
label = set.getAnnotation(type);
}
return label;
}
/**
* This will provide the contact type. The contact type is the
* class that is to be set and get on the object. This represents
* the return type for the get and the parameter for the set.
*
* @return this returns the type that this contact represents
*/
public Class getType() {
return type;
}
/**
* This provides the dependent class for the contact. This will
* actually represent a generic type for the actual type. For
* contacts that use a Collection type this will
* be the generic type parameter for that collection.
*
* @return this returns the dependent type for the contact
*/
public Class getDependent() {
return item;
}
/**
* This provides the dependent classes for the contact. This will
* typically represent a generic types for the actual type. For
* contacts that use a Map type this will be the
* generic type parameter for that map type declaration.
*
* @return this returns the dependent type for the contact
*/
public Class[] getDependents() {
return items;
}
/**
* This is used to acquire the name of the method. This returns
* the name of the method without the get, set or is prefix that
* represents the Java Bean method type. Also this decaptitalizes
* the resulting name. The result is used to represent the XML
* attribute of element within the class schema represented.
*
* @return this returns the name of the method represented
*/
public String getName() {
return name;
}
/**
* This is used to set the specified value on the provided object.
* The value provided must be an instance of the contact class so
* that it can be set without a runtime class compatibility error.
*
* @param source this is the object to set the value on
* @param value this is the value that is to be set on the object
*/
public void set(Object source, Object value) throws Exception{
Class type = getType();
if(set == null) {
throw new MethodException("Method '%s' of '%s' is read only", name, type);
}
set.getMethod().invoke(source, value);
}
/**
* This is used to get the specified value on the provided object.
* The value returned from this method will be an instance of the
* contact class type. If the returned object is of a different
* type then the serialization process will fail.
*
* @param source this is the object to acquire the value from
*
* @return this is the value that is acquired from the object
*/
public Object get(Object source) throws Exception {
return get.invoke(source);
}
/**
* This is used to describe the contact as it exists within the
* owning class. It is used to provide error messages that can
* be used to debug issues that occur when processing a contact.
* The string provided contains both the set and get methods.
*
* @return this returns a string representation of the contact
*/
public String toString() {
return String.format("method '%s'", name);
}
}