org.displaytag.util
Class LookupUtil

java.lang.Object
  org.displaytag.util.LookupUtil

public final class LookupUtil
extends java.lang.Object

Utility class with methods for object and properties retrieving.

Version:

$Id: LookupUtil.java 1081 2006-04-03 20:26:34Z fgiust $

Author:

Fabrizio Giustina

Method Summary

static java.lang.Object	getBeanProperty(java.lang.Object bean, java.lang.String name) Returns the value of a property in the given bean.
static java.lang.Object	getBeanValue(javax.servlet.jsp.PageContext pageContext, java.lang.String beanAndPropertyName, int scope) Read an object from the pagecontext with the specified scope and eventually lookup a property in it.
static java.lang.Object	getIndexedProperty(java.lang.Object bean, java.lang.String name) Return the value of the specified indexed property of the specified bean, with no type conversions.
static java.lang.Object	getProperty(java.lang.Object bean, java.lang.String name) Return the value of the (possibly nested) property of the specified name, for the specified bean, with no type conversions.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getBeanValue

public static java.lang.Object getBeanValue(javax.servlet.jsp.PageContext pageContext,
                                            java.lang.String beanAndPropertyName,
                                            int scope)
                                     throws ObjectLookupException

Read an object from the pagecontext with the specified scope and eventually lookup a property in it.

Parameters:

pageContext - PageContext

beanAndPropertyName - String expression with bean name and attributes

scope - One of the following values:

• PageContext.PAGE_SCOPE
• PageContext.REQUEST_SCOPE
• PageContext.SESSION_SCOPE
• PageContext.APPLICATION_SCOPE

Returns:

Object

Throws:

ObjectLookupException - for errors while retrieving a property in the bean

getBeanProperty

public static java.lang.Object getBeanProperty(java.lang.Object bean,
                                               java.lang.String name)
                                        throws ObjectLookupException

Returns the value of a property in the given bean.

Handle NestedNullException returning nulls and other exceptions returning ObjectLookupException.

Parameters:

bean - javabean

name - name of the property to read from the javabean

Returns:

Object

Throws:

ObjectLookupException - for errors while retrieving a property in the bean

getProperty

public static java.lang.Object getProperty(java.lang.Object bean,
                                           java.lang.String name)
                                    throws java.lang.IllegalAccessException,
                                           java.lang.reflect.InvocationTargetException,
                                           java.lang.NoSuchMethodException

Return the value of the (possibly nested) property of the specified name, for the specified bean, with no type conversions.

Parameters:

bean - Bean whose property is to be extracted

name - Possibly nested name of the property to be extracted

Returns:

Object

Throws:

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

java.lang.IllegalAccessException

BeanPropertyLookupException - in caso di errori nella lettura di propriet� del bean

getIndexedProperty

public static java.lang.Object getIndexedProperty(java.lang.Object bean,
                                                  java.lang.String name)
                                           throws java.lang.IllegalAccessException,
                                                  java.lang.reflect.InvocationTargetException,
                                                  java.lang.NoSuchMethodException

Return the value of the specified indexed property of the specified bean, with no type conversions. 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. In addition to supporting the JavaBeans specification, this method has been extended to support List objects as well.

Parameters:

bean - Bean whose property is to be extracted

name - propertyname[index] of the property value to be extracted

Returns:

Object

Throws:

java.lang.IllegalAccessException - if the caller does not have access to the property accessor method

java.lang.reflect.InvocationTargetException - if the property accessor method throws an exception

java.lang.NoSuchMethodException - if an accessor method for this propety cannot be found