com.feilong.lib.beanutils.BeanUtilsBean Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of feilong Show documentation
Show all versions of feilong Show documentation
feilong is a suite of core and expanded libraries that include utility classes, http, excel,cvs, io classes, and much much more.
/*
* 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 com.feilong.lib.beanutils;
import java.beans.IndexedPropertyDescriptor;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.commons.beanutils.DynaBean;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.feilong.lib.beanutils.expression.Resolver;
/**
*
* JavaBean property population methods.
*
*
*
* This class provides implementations for the utility methods in
* {@link BeanUtils}.
* Different instances can be used to isolate caches between classloaders
* and to vary the value converters registered.
*
*
* @version $Id$
* @see BeanUtils
* @since 1.7
*/
public class BeanUtilsBean{
/** The Constant log. */
private static final Logger LOGGER = LoggerFactory.getLogger(BeanUtilsBean.class);
// ------------------------------------------------------ Private Class Variables
/**
* Contains BeanUtilsBean instances indexed by context classloader.
*/
private static final ContextClassLoaderLocal BEANS_BY_CLASSLOADER = new ContextClassLoaderLocal(){
// Creates the default instance used when the context classloader is unavailable
@Override
protected BeanUtilsBean initialValue(){
return new BeanUtilsBean();
}
};
/**
* Gets the instance which provides the functionality for {@link BeanUtils}.
* This is a pseudo-singleton - an single instance is provided per (thread) context classloader.
* This mechanism provides isolation for web apps deployed in the same container.
*
* @return The (pseudo-singleton) BeanUtils bean instance
*/
public static BeanUtilsBean getInstance(){
return BEANS_BY_CLASSLOADER.get();
}
/**
* Sets the instance which provides the functionality for {@link BeanUtils}.
* This is a pseudo-singleton - an single instance is provided per (thread) context classloader.
* This mechanism provides isolation for web apps deployed in the same container.
*
* @param newInstance
* The (pseudo-singleton) BeanUtils bean instance
*/
public static void setInstance(final BeanUtilsBean newInstance){
BEANS_BY_CLASSLOADER.set(newInstance);
}
// --------------------------------------------------------- Attributes
/** Used to perform conversions between object types when setting properties */
private final ConvertUtilsBean convertUtilsBean;
/** Used to access properties */
private final PropertyUtilsBean propertyUtilsBean;
// --------------------------------------------------------- Constuctors
/**
*
* Constructs an instance using new property
* and conversion instances.
*
*/
public BeanUtilsBean(){
this(new ConvertUtilsBean(), new PropertyUtilsBean());
}
/**
*
* Constructs an instance using given conversion instances
* and new {@link PropertyUtilsBean} instance.
*
*
* @param convertUtilsBean
* use this ConvertUtilsBean
* to perform conversions from one object to another
*
* @since 1.8.0
*/
public BeanUtilsBean(final ConvertUtilsBean convertUtilsBean){
this(convertUtilsBean, new PropertyUtilsBean());
}
/**
*
* Constructs an instance using given property and conversion instances.
*
*
* @param convertUtilsBean
* use this ConvertUtilsBean
* to perform conversions from one object to another
* @param propertyUtilsBean
* use this PropertyUtilsBean
* to access properties
*/
public BeanUtilsBean(final ConvertUtilsBean convertUtilsBean, final PropertyUtilsBean propertyUtilsBean){
this.convertUtilsBean = convertUtilsBean;
this.propertyUtilsBean = propertyUtilsBean;
}
// --------------------------------------------------------- Public Methods
/**
*
* Clone a bean based on the available property getters and setters,
* even if the bean class itself does not implement Cloneable.
*
*
*
* Note: this method creates a shallow clone.
* In other words, any objects referred to by the bean are shared with the clone
* rather than being cloned in turn.
*
*
* @param bean
* Bean to be cloned
* @return the cloned bean
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InstantiationException
* if a new instance of the bean's
* class cannot be instantiated
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public Object cloneBean(final Object bean)
throws IllegalAccessException,InstantiationException,InvocationTargetException,NoSuchMethodException{
if (LOGGER.isDebugEnabled()){
LOGGER.debug("Cloning bean: " + bean.getClass().getName());
}
Object newBean = null;
if (bean instanceof DynaBean){
newBean = ((DynaBean) bean).getDynaClass().newInstance();
}else{
newBean = bean.getClass().newInstance();
}
getPropertyUtils().copyProperties(newBean, bean);
return (newBean);
}
/**
*
* Copy property values from the origin bean to the destination bean
* for all cases where the property names are the same. For each
* property, a conversion is attempted as necessary. All combinations of
* standard JavaBeans and DynaBeans as origin and destination are
* supported. Properties that exist in the origin bean, but do not exist
* in the destination bean (or are read-only in the destination bean) are
* silently ignored.
*
*
*
* If the origin "bean" is actually a Map, it is assumed
* to contain String-valued simple property names as the keys, pointing at
* the corresponding property values that will be converted (if necessary)
* and set in the destination bean. Note that this method
* is intended to perform a "shallow copy" of the properties and so complex
* properties (for example, nested ones) will not be copied.
*
*
*
* This method differs from populate(), which
* was primarily designed for populating JavaBeans from the map of request
* parameters retrieved on an HTTP request, is that no scalar->indexed
* or indexed->scalar manipulations are performed. If the origin property
* is indexed, the destination property must be also.
*
*
*
* If you know that no type conversions are required, the
* copyProperties() method in {@link PropertyUtils} will
* execute faster than this method.
*
*
*
* FIXME - Indexed and mapped properties that do not
* have getter and setter methods for the underlying array or Map are not
* copied by this method.
*
*
* @param dest
* Destination bean whose properties are modified
* @param orig
* Origin bean whose properties are retrieved
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws IllegalArgumentException
* if the dest or
* orig argument is null or if the dest
* property type is different from the source type and the relevant
* converter has not been registered.
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
*/
public void copyProperties(final Object dest,final Object orig) throws IllegalAccessException,InvocationTargetException{
// Validate existence of the specified beans
if (dest == null){
throw new IllegalArgumentException("No destination bean specified");
}
if (orig == null){
throw new IllegalArgumentException("No origin bean specified");
}
if (LOGGER.isDebugEnabled()){
LOGGER.debug("BeanUtils.copyProperties(" + dest + ", " + orig + ")");
}
// Copy the properties, converting as necessary
if (orig instanceof DynaBean){
final DynaProperty[] origDescriptors = ((DynaBean) orig).getDynaClass().getDynaProperties();
for (DynaProperty origDescriptor : origDescriptors){
final String name = origDescriptor.getName();
// Need to check isReadable() for WrapDynaBean
// (see Jira issue# BEANUTILS-61)
if (getPropertyUtils().isReadable(orig, name) && getPropertyUtils().isWriteable(dest, name)){
final Object value = ((DynaBean) orig).get(name);
copyProperty(dest, name, value);
}
}
}else if (orig instanceof Map){
@SuppressWarnings("unchecked")
final
// Map properties are always of type
Map propMap = (Map) orig;
for (final Map.Entry entry : propMap.entrySet()){
final String name = entry.getKey();
if (getPropertyUtils().isWriteable(dest, name)){
copyProperty(dest, name, entry.getValue());
}
}
}else /* if (orig is a standard JavaBean) */ {
final PropertyDescriptor[] origDescriptors = getPropertyUtils().getPropertyDescriptors(orig);
for (PropertyDescriptor origDescriptor : origDescriptors){
final String name = origDescriptor.getName();
if ("class".equals(name)){
continue; // No point in trying to set an object's class
}
if (getPropertyUtils().isReadable(orig, name) && getPropertyUtils().isWriteable(dest, name)){
try{
final Object value = getPropertyUtils().getSimpleProperty(orig, name);
copyProperty(dest, name, value);
}catch (final NoSuchMethodException e){
// Should not happen
}
}
}
}
}
/**
*
* Copy the specified property value to the specified destination bean,
* performing any type conversion that is required. If the specified
* bean does not have a property of the specified name, or the property
* is read only on the destination bean, return without
* doing anything. If you have custom destination property types, register
* {@link Converter}s for them by calling the register()
* method of {@link ConvertUtils}.
*
*
*
* IMPLEMENTATION RESTRICTIONS:
*
*
* - Does not support destination properties that are indexed,
* but only an indexed setter (as opposed to an array setter)
* is available.
* - Does not support destination properties that are mapped,
* but only a keyed setter (as opposed to a Map setter)
* is available.
* - The desired property type of a mapped setter cannot be
* determined (since Maps support any data type), so no conversion
* will be performed.
*
*
* @param bean
* Bean on which setting is to be performed
* @param name
* Property name (can be nested/indexed/mapped/combo)
* @param value
* Value to be set
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
*/
public void copyProperty(final Object bean,String name,Object value) throws IllegalAccessException,InvocationTargetException{
// Trace logging (if enabled)
if (LOGGER.isTraceEnabled()){
final StringBuilder sb = new StringBuilder(" copyProperty(");
sb.append(bean);
sb.append(", ");
sb.append(name);
sb.append(", ");
if (value == null){
sb.append("");
}else if (value instanceof String){
sb.append((String) value);
}else if (value instanceof String[]){
final String[] values = (String[]) value;
sb.append('[');
for (int i = 0; i < values.length; i++){
if (i > 0){
sb.append(',');
}
sb.append(values[i]);
}
sb.append(']');
}else{
sb.append(value.toString());
}
sb.append(')');
LOGGER.trace(sb.toString());
}
// Resolve any nested expression to get the actual target bean
Object target = bean;
final Resolver resolver = getPropertyUtils().getResolver();
while (resolver.hasNested(name)){
try{
target = getPropertyUtils().getProperty(target, resolver.next(name));
name = resolver.remove(name);
}catch (final NoSuchMethodException e){
return; // Skip this property setter
}
}
if (LOGGER.isTraceEnabled()){
LOGGER.trace(" Target bean = " + target);
LOGGER.trace(" Target name = " + name);
}
// Declare local variables we will require
final String propName = resolver.getProperty(name); // Simple name of target property
Class type = null; // Java type of target property
final int index = resolver.getIndex(name); // Indexed subscript value (if any)
final String key = resolver.getKey(name); // Mapped key value (if any)
// Calculate the target property type
if (target instanceof DynaBean){
final DynaClass dynaClass = ((DynaBean) target).getDynaClass();
final DynaProperty dynaProperty = dynaClass.getDynaProperty(propName);
if (dynaProperty == null){
return; // Skip this property setter
}
type = dynaPropertyType(dynaProperty, value);
}else{
PropertyDescriptor descriptor = null;
try{
descriptor = getPropertyUtils().getPropertyDescriptor(target, name);
if (descriptor == null){
return; // Skip this property setter
}
}catch (final NoSuchMethodException e){
return; // Skip this property setter
}
type = descriptor.getPropertyType();
if (type == null){
// Most likely an indexed setter on a POJB only
if (LOGGER.isTraceEnabled()){
LOGGER.trace(" target type for property '" + propName + "' is null, so skipping ths setter");
}
return;
}
}
if (LOGGER.isTraceEnabled()){
LOGGER.trace(" target propName=" + propName + ", type=" + type + ", index=" + index + ", key=" + key);
}
// Convert the specified value to the required type and store it
if (index >= 0){ // Destination must be indexed
value = convertForCopy(value, type.getComponentType());
try{
getPropertyUtils().setIndexedProperty(target, propName, index, value);
}catch (final NoSuchMethodException e){
throw new InvocationTargetException(e, "Cannot set " + propName);
}
}else if (key != null){ // Destination must be mapped
// Maps do not know what the preferred data type is,
// so perform no conversions at all
// FIXME - should we create or support a TypedMap?
try{
getPropertyUtils().setMappedProperty(target, propName, key, value);
}catch (final NoSuchMethodException e){
throw new InvocationTargetException(e, "Cannot set " + propName);
}
}else{ // Destination must be simple
value = convertForCopy(value, type);
try{
getPropertyUtils().setSimpleProperty(target, propName, value);
}catch (final NoSuchMethodException e){
throw new InvocationTargetException(e, "Cannot set " + propName);
}
}
}
/**
*
* Return the entire set of properties for which the specified bean
* provides a read method. This map contains the to String
* converted property values for all properties for which a read method
* is provided (i.e. where the getReadMethod() returns non-null).
*
*
*
* This map can be fed back to a call to
* BeanUtils.populate() to reconsitute the same set of
* properties, modulo differences for read-only and write-only
* properties, but only if there are no indexed properties.
*
*
*
* Warning: if any of the bean property implementations
* contain (directly or indirectly) a call to this method then
* a stack overflow may result. For example:
*
* class MyBean
* {
* public Map getParameterMap()
* {
* BeanUtils.describe(this);
* }
* }
* getParametersMap
* is called. It is recommended that such methods are given alternative
* names (for example, parametersMap).
*
*
* @param bean
* Bean whose properties are to be extracted
* @return Map of property descriptors
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public Map describe(final Object bean) throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
if (bean == null){
// return (Collections.EMPTY_MAP);
return (new java.util.HashMap<>());
}
if (LOGGER.isDebugEnabled()){
LOGGER.debug("Describing bean: " + bean.getClass().getName());
}
final Map description = new HashMap<>();
if (bean instanceof DynaBean){
final DynaProperty[] descriptors = ((DynaBean) bean).getDynaClass().getDynaProperties();
for (DynaProperty descriptor : descriptors){
final String name = descriptor.getName();
description.put(name, getProperty(bean, name));
}
}else{
final PropertyDescriptor[] descriptors = getPropertyUtils().getPropertyDescriptors(bean);
final Class clazz = bean.getClass();
for (PropertyDescriptor descriptor : descriptors){
final String name = descriptor.getName();
getPropertyUtils();
if (PropertyUtilsBean.getReadMethod(clazz, descriptor) != null){
description.put(name, getProperty(bean, name));
}
}
}
return (description);
}
/**
* Return the value of the specified array property of the specified
* bean, as a String array.
*
* @param bean
* Bean whose property is to be extracted
* @param name
* Name of the property to be extracted
* @return The array property value
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String[] getArrayProperty(final Object bean,final String name)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
final Object value = getPropertyUtils().getProperty(bean, name);
if (value == null){
return (null);
}else if (value instanceof Collection){
final ArrayList values = new ArrayList<>();
for (final Object item : (Collection) value){
if (item == null){
values.add(null);
}else{
// convert to string using convert utils
values.add(getConvertUtils().convert(item));
}
}
return (values.toArray(new String[values.size()]));
}else if (value.getClass().isArray()){
final int n = Array.getLength(value);
final String[] results = new String[n];
for (int i = 0; i < n; i++){
final Object item = Array.get(value, i);
if (item == null){
results[i] = null;
}else{
// convert to string using convert utils
results[i] = getConvertUtils().convert(item);
}
}
return (results);
}else{
final String[] results = new String[1];
results[0] = getConvertUtils().convert(value);
return (results);
}
}
/**
* Return the value of the specified indexed property of the specified
* bean, as a String. The zero-relative index of the
* required value must be included (in square brackets) as a suffix to
* the property name, or IllegalArgumentException will be
* thrown.
*
* @param bean
* Bean whose property is to be extracted
* @param name
* propertyname[index] of the property value
* to be extracted
* @return The indexed property's value, converted to a String
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String getIndexedProperty(final Object bean,final String name)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
final Object value = getPropertyUtils().getIndexedProperty(bean, name);
return (getConvertUtils().convert(value));
}
/**
* Return the value of the specified indexed property of the specified
* bean, as a String. The index is specified as a method parameter and
* must *not* be included in the property name expression
*
* @param bean
* Bean whose property is to be extracted
* @param name
* Simple property name of the property value to be extracted
* @param index
* Index of the property value to be extracted
* @return The indexed property's value, converted to a String
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String getIndexedProperty(final Object bean,final String name,final int index)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
final Object value = getPropertyUtils().getIndexedProperty(bean, name, index);
return (getConvertUtils().convert(value));
}
/**
* Return the value of the specified indexed property of the specified
* bean, as a String. The String-valued key of the required value
* must be included (in parentheses) as a suffix to
* the property name, or IllegalArgumentException will be
* thrown.
*
* @param bean
* Bean whose property is to be extracted
* @param name
* propertyname(index) of the property value
* to be extracted
* @return The mapped property's value, converted to a String
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String getMappedProperty(final Object bean,final String name)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
final Object value = getPropertyUtils().getMappedProperty(bean, name);
return (getConvertUtils().convert(value));
}
/**
* Return the value of the specified mapped property of the specified
* bean, as a String. The key is specified as a method parameter and
* must *not* be included in the property name expression
*
* @param bean
* Bean whose property is to be extracted
* @param name
* Simple property name of the property value to be extracted
* @param key
* Lookup key of the property value to be extracted
* @return The mapped property's value, converted to a String
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String getMappedProperty(final Object bean,final String name,final String key)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
final Object value = getPropertyUtils().getMappedProperty(bean, name, key);
return (getConvertUtils().convert(value));
}
/**
* Return the value of the (possibly nested) property of the specified
* name, for the specified bean, as a String.
*
* @param bean
* Bean whose property is to be extracted
* @param name
* Possibly nested name of the property to be extracted
* @return The nested property's value, converted to a String
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws IllegalArgumentException
* if a nested reference to a
* property returns null
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String getNestedProperty(final Object bean,final String name)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
final Object value = getPropertyUtils().getProperty(bean, name);
return getConvertUtils().convert(value);
}
/**
* Return the value of the specified property of the specified bean,
* no matter which property reference format is used, as a String.
*
* @param bean
* Bean whose property is to be extracted
* @param name
* Possibly indexed and/or nested name of the property
* to be extracted
* @return The property's value, converted to a String
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String getProperty(final Object bean,final String name)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
return (getNestedProperty(bean, name));
}
/**
* Return the value of the specified simple property of the specified
* bean, converted to a String.
*
* @param bean
* Bean whose property is to be extracted
* @param name
* Name of the property to be extracted
* @return The property's value, converted to a String
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
* @throws NoSuchMethodException
* if an accessor method for this
* property cannot be found
*/
public String getSimpleProperty(final Object bean,final String name)
throws IllegalAccessException,InvocationTargetException,NoSuchMethodException{
final Object value = getPropertyUtils().getSimpleProperty(bean, name);
return (getConvertUtils().convert(value));
}
/**
*
* Populate the JavaBeans properties of the specified bean, based on
* the specified name/value pairs. This method uses Java reflection APIs
* to identify corresponding "property setter" method names, and deals
* with setter arguments of type String, boolean,
* int, long, float, and
* double. In addition, array setters for these types (or the
* corresponding primitive types) can also be identified.
*
*
*
* The particular setter method to be called for each property is
* determined using the usual JavaBeans introspection mechanisms. Thus,
* you may identify custom setter methods using a BeanInfo class that is
* associated with the class of the bean itself. If no such BeanInfo
* class is available, the standard method name conversion ("set" plus
* the capitalized name of the property in question) is used.
*
*
*
* NOTE: It is contrary to the JavaBeans Specification
* to have more than one setter method (with different argument
* signatures) for the same property.
*
*
*
* WARNING - The logic of this method is customized
* for extracting String-based request parameters from an HTTP request.
* It is probably not what you want for general property copying with
* type conversion. For that purpose, check out the
* copyProperties() method instead.
*
*
* @param bean
* JavaBean whose properties are being populated
* @param properties
* Map keyed by property name, with the
* corresponding (String or String[]) value(s) to be set
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
*/
public void populate(final Object bean,final Map properties)
throws IllegalAccessException,InvocationTargetException{
// Do nothing unless both arguments have been specified
if ((bean == null) || (properties == null)){
return;
}
if (LOGGER.isDebugEnabled()){
LOGGER.debug("BeanUtils.populate(" + bean + ", " + properties + ")");
}
// Loop through the property name/value pairs to be set
for (final Map.Entry entry : properties.entrySet()){
// Identify the property name and value(s) to be assigned
final String name = entry.getKey();
if (name == null){
continue;
}
// Perform the assignment for this property
setProperty(bean, name, entry.getValue());
}
}
/**
*
* Set the specified property value, performing type conversions as
* required to conform to the type of the destination property.
*
*
*
* If the property is read only then the method returns
* without throwing an exception.
*
*
*
* If null is passed into a property expecting a primitive value,
* then this will be converted as if it were a null string.
*
*
*
* WARNING - The logic of this method is customized
* to meet the needs of populate(), and is probably not what
* you want for general property copying with type conversion. For that
* purpose, check out the copyProperty() method instead.
*
*
*
* WARNING - PLEASE do not modify the behavior of this
* method without consulting with the Struts developer community. There
* are some subtleties to its functionality that are not documented in the
* Javadoc description above, yet are vital to the way that Struts utilizes
* this method.
*
*
* @param bean
* Bean on which setting is to be performed
* @param name
* Property name (can be nested/indexed/mapped/combo)
* @param value
* Value to be set
*
* @throws IllegalAccessException
* if the caller does not have
* access to the property accessor method
* @throws InvocationTargetException
* if the property accessor method
* throws an exception
*/
public void setProperty(final Object bean,String name,final Object value) throws IllegalAccessException,InvocationTargetException{
// Trace logging (if enabled)
if (LOGGER.isTraceEnabled()){
final StringBuilder sb = new StringBuilder(" setProperty(");
sb.append(bean);
sb.append(", ");
sb.append(name);
sb.append(", ");
if (value == null){
sb.append("");
}else if (value instanceof String){
sb.append((String) value);
}else if (value instanceof String[]){
final String[] values = (String[]) value;
sb.append('[');
for (int i = 0; i < values.length; i++){
if (i > 0){
sb.append(',');
}
sb.append(values[i]);
}
sb.append(']');
}else{
sb.append(value.toString());
}
sb.append(')');
LOGGER.trace(sb.toString());
}
// Resolve any nested expression to get the actual target bean
Object target = bean;
final Resolver resolver = getPropertyUtils().getResolver();
while (resolver.hasNested(name)){
try{
target = getPropertyUtils().getProperty(target, resolver.next(name));
if (target == null){ // the value of a nested property is null
return;
}
name = resolver.remove(name);
}catch (final NoSuchMethodException e){
return; // Skip this property setter
}
}
if (LOGGER.isTraceEnabled()){
LOGGER.trace(" Target bean = " + target);
LOGGER.trace(" Target name = " + name);
}
// Declare local variables we will require
final String propName = resolver.getProperty(name); // Simple name of target property
Class type = null; // Java type of target property
final int index = resolver.getIndex(name); // Indexed subscript value (if any)
final String key = resolver.getKey(name); // Mapped key value (if any)
// Calculate the property type
if (target instanceof DynaBean){
final DynaClass dynaClass = ((DynaBean) target).getDynaClass();
final DynaProperty dynaProperty = dynaClass.getDynaProperty(propName);
if (dynaProperty == null){
return; // Skip this property setter
}
type = dynaPropertyType(dynaProperty, value);
if (index >= 0 && List.class.isAssignableFrom(type)){
type = Object.class;
}
}else if (target instanceof Map){
type = Object.class;
}else if (target != null && target.getClass().isArray() && index >= 0){
type = Array.get(target, index).getClass();
}else{
PropertyDescriptor descriptor = null;
try{
descriptor = getPropertyUtils().getPropertyDescriptor(target, name);
if (descriptor == null){
return; // Skip this property setter
}
}catch (final NoSuchMethodException e){
return; // Skip this property setter
}
if (descriptor instanceof MappedPropertyDescriptor){
if (((MappedPropertyDescriptor) descriptor).getMappedWriteMethod() == null){
if (LOGGER.isDebugEnabled()){
LOGGER.debug("Skipping read-only property");
}
return; // Read-only, skip this property setter
}
type = ((MappedPropertyDescriptor) descriptor).getMappedPropertyType();
}else if (index >= 0 && descriptor instanceof IndexedPropertyDescriptor){
if (((IndexedPropertyDescriptor) descriptor).getIndexedWriteMethod() == null){
if (LOGGER.isDebugEnabled()){
LOGGER.debug("Skipping read-only property");
}
return; // Read-only, skip this property setter
}
type = ((IndexedPropertyDescriptor) descriptor).getIndexedPropertyType();
}else if (index >= 0 && List.class.isAssignableFrom(descriptor.getPropertyType())){
type = Object.class;
}else if (key != null){
if (descriptor.getReadMethod() == null){
if (LOGGER.isDebugEnabled()){
LOGGER.debug("Skipping read-only property");
}
return; // Read-only, skip this property setter
}
type = (value == null) ? Object.class : value.getClass();
}else{
if (descriptor.getWriteMethod() == null){
if (LOGGER.isDebugEnabled()){
LOGGER.debug("Skipping read-only property");
}
return; // Read-only, skip this property setter
}
type = descriptor.getPropertyType();
}
}
// Convert the specified value to the required type
Object newValue = null;
if (type.isArray() && (index < 0)){ // Scalar value into array
if (value == null){
final String[] values = new String[1];
values[0] = null;
newValue = getConvertUtils().convert(values, type);
}else if (value instanceof String){
newValue = getConvertUtils().convert(value, type);
}else if (value instanceof String[]){
newValue = getConvertUtils().convert((String[]) value, type);
}else{
newValue = convert(value, type);
}
}else if (type.isArray()){ // Indexed value into array
if (value instanceof String || value == null){
newValue = getConvertUtils().convert((String) value, type.getComponentType());
}else if (value instanceof String[]){
newValue = getConvertUtils().convert(((String[]) value)[0], type.getComponentType());
}else{
newValue = convert(value, type.getComponentType());
}
}else{ // Value into scalar
if (value instanceof String){
newValue = getConvertUtils().convert((String) value, type);
}else if (value instanceof String[]){
newValue = getConvertUtils().convert(((String[]) value)[0], type);
}else{
newValue = convert(value, type);
}
}
// Invoke the setter method
try{
getPropertyUtils().setProperty(target, name, newValue);
}catch (final NoSuchMethodException e){
throw new InvocationTargetException(e, "Cannot set " + propName);
}
}
/**
* Gets the ConvertUtilsBean instance used to perform the conversions.
*
* @return The ConvertUtils bean instance
*/
public ConvertUtilsBean getConvertUtils(){
return convertUtilsBean;
}
/**
* Gets the PropertyUtilsBean instance used to access properties.
*
* @return The ConvertUtils bean instance
*/
public PropertyUtilsBean getPropertyUtils(){
return propertyUtilsBean;
}
/**
*
* Convert the value to an object of the specified class (if
* possible).
*
*
* @param value
* Value to be converted (may be null)
* @param type
* Class of the value to be converted to
* @return The converted value
*
* @throws ConversionException
* if thrown by an underlying Converter
* @since 1.8.0
*/
protected Object convert(final Object value,final Class type){
final Converter converter = getConvertUtils().lookup(type);
if (converter != null){
LOGGER.trace(" USING CONVERTER " + converter);
return converter.convert(type, value);
}
return value;
}
/**
* Performs a type conversion of a property value before it is copied to a target
* bean. This method delegates to {@link #convert(Object, Class)}, but null
* values are not converted. This causes null values to be copied verbatim.
*
* @param value
* the value to be converted and copied
* @param type
* the target type of the conversion
* @return the converted value
*/
private Object convertForCopy(final Object value,final Class type){
return (value != null) ? convert(value, type) : value;
}
/**
* Determines the type of a {@code DynaProperty}. Here a special treatment
* is needed for mapped properties.
*
* @param dynaProperty
* the property descriptor
* @param value
* the value object to be set for this property
* @return the type of this property
*/
private static Class dynaPropertyType(final DynaProperty dynaProperty,final Object value){
if (!dynaProperty.isMapped()){
return dynaProperty.getType();
}
return (value == null) ? String.class : value.getClass();
}
}