alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Commons Beanutils example source code file (BasicDynaBean.java)

This example Commons Beanutils source code file (BasicDynaBean.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Commons Beanutils tags/keywords

dynaproperty, hashmap, illegalargumentexception, illegalargumentexception, io, list, map, map, no, non-mapped, nullpointerexception, nullpointerexception, object, object, reflection, string, util

The Commons Beanutils BasicDynaBean.java source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.commons.beanutils;


import java.io.Serializable;
import java.lang.reflect.Array;
import java.util.HashMap;
import java.util.List;
import java.util.Map;


/**
 * <p>Minimal implementation of the DynaBean interface.  Can be
 * used as a convenience base class for more sophisticated implementations.</p>
 *
 * <p>IMPLEMENTATION NOTE - Instances of this class that are
 * accessed from multiple threads simultaneously need to be synchronized.</p>
 *
 * <p>IMPLEMENTATION NOTE - Instances of this class can be
 * successfully serialized and deserialized <strong>ONLY if all
 * property values are <code>Serializable.

* * @author Craig McClanahan * @version $Revision: 926529 $ $Date: 2010-03-23 11:44:24 +0000 (Tue, 23 Mar 2010) $ */ public class BasicDynaBean implements DynaBean, Serializable { // ---------------------------------------------------------- Constructors /** * Construct a new <code>DynaBean associated with the specified * <code>DynaClass instance. * * @param dynaClass The DynaClass we are associated with */ public BasicDynaBean(DynaClass dynaClass) { super(); this.dynaClass = dynaClass; } // ---------------------------------------------------- Instance Variables /** * The <code>DynaClass "base class" that this DynaBean * is associated with. */ protected DynaClass dynaClass = null; /** * The set of property values for this DynaBean, keyed by property name. */ protected HashMap values = new HashMap(); /** Map decorator for this DynaBean */ private transient Map mapDecorator; /** * Return a Map representation of this DynaBean. * </p> * This, for example, could be used in JSTL in the following way to access * a DynaBean's <code>fooProperty: * <ul>
  • ${myDynaBean.map.fooProperty}
  • * * @return a Map representation of this DynaBean * @since 1.8.0 */ public Map getMap() { // cache the Map if (mapDecorator == null) { mapDecorator = new DynaBeanMapDecorator(this); } return mapDecorator; } // ------------------------------------------------------ DynaBean Methods /** * Does the specified mapped property contain a value for the specified * key value? * * @param name Name of the property to check * @param key Name of the key to check * @return <code>true if the mapped property contains a value for * the specified key, otherwise <code>false * * @exception IllegalArgumentException if there is no property * of the specified name */ public boolean contains(String name, String key) { Object value = values.get(name); if (value == null) { throw new NullPointerException ("No mapped value for '" + name + "(" + key + ")'"); } else if (value instanceof Map) { return (((Map) value).containsKey(key)); } else { throw new IllegalArgumentException ("Non-mapped property for '" + name + "(" + key + ")'"); } } /** * Return the value of a simple property with the specified name. * * @param name Name of the property whose value is to be retrieved * @return The property's value * * @exception IllegalArgumentException if there is no property * of the specified name */ public Object get(String name) { // Return any non-null value for the specified property Object value = values.get(name); if (value != null) { return (value); } // Return a null value for a non-primitive property Class type = getDynaProperty(name).getType(); if (!type.isPrimitive()) { return (value); } // Manufacture default values for primitive properties if (type == Boolean.TYPE) { return (Boolean.FALSE); } else if (type == Byte.TYPE) { return (new Byte((byte) 0)); } else if (type == Character.TYPE) { return (new Character((char) 0)); } else if (type == Double.TYPE) { return (new Double(0.0)); } else if (type == Float.TYPE) { return (new Float((float) 0.0)); } else if (type == Integer.TYPE) { return (new Integer(0)); } else if (type == Long.TYPE) { return (new Long(0)); } else if (type == Short.TYPE) { return (new Short((short) 0)); } else { return (null); } } /** * Return the value of an indexed property with the specified name. * * @param name Name of the property whose value is to be retrieved * @param index Index of the value to be retrieved * @return The indexed property's value * * @exception IllegalArgumentException if there is no property * of the specified name * @exception IllegalArgumentException if the specified property * exists, but is not indexed * @exception IndexOutOfBoundsException if the specified index * is outside the range of the underlying property * @exception NullPointerException if no array or List has been * initialized for this property */ public Object get(String name, int index) { Object value = values.get(name); if (value == null) { throw new NullPointerException ("No indexed value for '" + name + "[" + index + "]'"); } else if (value.getClass().isArray()) { return (Array.get(value, index)); } else if (value instanceof List) { return ((List) value).get(index); } else { throw new IllegalArgumentException ("Non-indexed property for '" + name + "[" + index + "]'"); } } /** * Return the value of a mapped property with the specified name, * or <code>null if there is no value for the specified key. * * @param name Name of the property whose value is to be retrieved * @param key Key of the value to be retrieved * @return The mapped property's value * * @exception IllegalArgumentException if there is no property * of the specified name * @exception IllegalArgumentException if the specified property * exists, but is not mapped */ public Object get(String name, String key) { Object value = values.get(name); if (value == null) { throw new NullPointerException ("No mapped value for '" + name + "(" + key + ")'"); } else if (value instanceof Map) { return (((Map) value).get(key)); } else { throw new IllegalArgumentException ("Non-mapped property for '" + name + "(" + key + ")'"); } } /** * Return the <code>DynaClass instance that describes the set of * properties available for this DynaBean. * * @return The associated DynaClass */ public DynaClass getDynaClass() { return (this.dynaClass); } /** * Remove any existing value for the specified key on the * specified mapped property. * * @param name Name of the property for which a value is to * be removed * @param key Key of the value to be removed * * @exception IllegalArgumentException if there is no property * of the specified name */ public void remove(String name, String key) { Object value = values.get(name); if (value == null) { throw new NullPointerException ("No mapped value for '" + name + "(" + key + ")'"); } else if (value instanceof Map) { ((Map) value).remove(key); } else { throw new IllegalArgumentException ("Non-mapped property for '" + name + "(" + key + ")'"); } } /** * Set the value of a simple property with the specified name. * * @param name Name of the property whose value is to be set * @param value Value to which this property is to be set * * @exception ConversionException if the specified value cannot be * converted to the type required for this property * @exception IllegalArgumentException if there is no property * of the specified name * @exception NullPointerException if an attempt is made to set a * primitive property to null */ public void set(String name, Object value) { DynaProperty descriptor = getDynaProperty(name); if (value == null) { if (descriptor.getType().isPrimitive()) { throw new NullPointerException ("Primitive value for '" + name + "'"); } } else if (!isAssignable(descriptor.getType(), value.getClass())) { throw new ConversionException ("Cannot assign value of type '" + value.getClass().getName() + "' to property '" + name + "' of type '" + descriptor.getType().getName() + "'"); } values.put(name, value); } /** * Set the value of an indexed property with the specified name. * * @param name Name of the property whose value is to be set * @param index Index of the property to be set * @param value Value to which this property is to be set * * @exception ConversionException if the specified value cannot be * converted to the type required for this property * @exception IllegalArgumentException if there is no property * of the specified name * @exception IllegalArgumentException if the specified property * exists, but is not indexed * @exception IndexOutOfBoundsException if the specified index * is outside the range of the underlying property */ public void set(String name, int index, Object value) { Object prop = values.get(name); if (prop == null) { throw new NullPointerException ("No indexed value for '" + name + "[" + index + "]'"); } else if (prop.getClass().isArray()) { Array.set(prop, index, value); } else if (prop instanceof List) { try { ((List) prop).set(index, value); } catch (ClassCastException e) { throw new ConversionException(e.getMessage()); } } else { throw new IllegalArgumentException ("Non-indexed property for '" + name + "[" + index + "]'"); } } /** * Set the value of a mapped property with the specified name. * * @param name Name of the property whose value is to be set * @param key Key of the property to be set * @param value Value to which this property is to be set * * @exception ConversionException if the specified value cannot be * converted to the type required for this property * @exception IllegalArgumentException if there is no property * of the specified name * @exception IllegalArgumentException if the specified property * exists, but is not mapped */ public void set(String name, String key, Object value) { Object prop = values.get(name); if (prop == null) { throw new NullPointerException ("No mapped value for '" + name + "(" + key + ")'"); } else if (prop instanceof Map) { ((Map) prop).put(key, value); } else { throw new IllegalArgumentException ("Non-mapped property for '" + name + "(" + key + ")'"); } } // ------------------------------------------------------ Protected Methods /** * Return the property descriptor for the specified property name. * * @param name Name of the property for which to retrieve the descriptor * @return The property descriptor * * @exception IllegalArgumentException if this is not a valid property * name for our DynaClass */ protected DynaProperty getDynaProperty(String name) { DynaProperty descriptor = getDynaClass().getDynaProperty(name); if (descriptor == null) { throw new IllegalArgumentException ("Invalid property name '" + name + "'"); } return (descriptor); } /** * Is an object of the source class assignable to the destination class? * * @param dest Destination class * @param source Source class * @return <code>true if the source class is assignable to the * destination class, otherwise <code>false */ protected boolean isAssignable(Class dest, Class source) { if (dest.isAssignableFrom(source) || ((dest == Boolean.TYPE) && (source == Boolean.class)) || ((dest == Byte.TYPE) && (source == Byte.class)) || ((dest == Character.TYPE) && (source == Character.class)) || ((dest == Double.TYPE) && (source == Double.class)) || ((dest == Float.TYPE) && (source == Float.class)) || ((dest == Integer.TYPE) && (source == Integer.class)) || ((dest == Long.TYPE) && (source == Long.class)) || ((dest == Short.TYPE) && (source == Short.class))) { return (true); } else { return (false); } } }

    Other Commons Beanutils examples (source code examples)

    Here is a short list of links related to this Commons Beanutils BasicDynaBean.java source code file:

    ... this post is sponsored by my books ...

    #1 New Release!

    FP Best Seller

     

    new blog posts

     

    Copyright 1998-2024 Alvin Alexander, alvinalexander.com
    All Rights Reserved.

    A percentage of advertising revenue from
    pages under the /java/jwarehouse URI on this website is
    paid back to open source projects.