org.apache.sling.scripting.sightly.compiler.util

Class ObjectModel

java.lang.Object

org.apache.sling.scripting.sightly.compiler.util.ObjectModel

public final class ObjectModel
extends java.lang.Object

The ObjectModel class provides various static models for object conversion and object property resolution.

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.Set<java.lang.Class<?>>	PRIMITIVE_CLASSES A Set that stores all the supported primitive classes.

Method Summary

Modifier and Type	Method and Description
static java.lang.String	collectionToString(java.util.Collection<?> collection) Converts the passed collection to a comma separated values String representation.
static java.lang.reflect.Method	findBeanMethod(java.lang.Class<?> cls, java.lang.String baseName) Given a bean class and a base method name, this method will try to find a public method without parameters that is named: baseName get + BaseName is + BaseName
static java.util.Collection<java.lang.Object>	fromIterator(java.util.Iterator<java.lang.Object> iterator) Given an iterator, this method will return a Collection.
static java.lang.Object	getField(java.lang.Object object, java.lang.String fieldName) Given an object, this method will return the value of the public field identified by fieldName.
static java.lang.Object	getIndex(java.lang.Object object, int index) Given an indexable object (i.e.
static java.lang.Object	invokeBeanMethod(java.lang.Object object, java.lang.String methodName) Given a bean object, this method will invoke the public method without parameters identified by methodName and return the invocation's result.
static boolean	isMethodAllowed(java.lang.reflect.Method method) Returns true if the method is not one of the Object's class declared methods, with the exception of Object.toString().
static boolean	isPrimitive(java.lang.Object object) Checks if the provided object is an instance of a primitive class.
static java.lang.Object	resolveProperty(java.lang.Object target, java.lang.Object property) Given the target object, this method attempts to resolve and return the value of the passed property.
static boolean	toBoolean(java.lang.Object object) Converts the given object to a boolean value, applying the following rules: if the object is null the returned value is false if the object is a Number the method will return false only if the number's value is 0 if the String representation of the object is equal irrespective of its casing to "true", the method will return true if the object is a Collection or a Map, the method will return true only if the collection / map is not empty if the object is an array, the method will return true only if the array is not empty
static java.util.Collection<java.lang.Object>	toCollection(java.lang.Object object) Forces the conversion of the passed object to a collection, according to the following rules: if the object is null an empty collection will be returned if the object is an array a list transformation of the array will be returned if the object is a Collection the object itself will be returned if the object is an instance of a Map the map's key set will be returned (see Map.keySet()) if the object is an instance of an Enumeration a list transformation will be returned if the object is an instance of an Iterator or Iterable the result of fromIterator(Iterator) will be returned if the object is an instance of a String or Number a Collection containing only this object will be returned any other case not covered by the previous rules will result in an empty Collection
static java.lang.Number	toNumber(java.lang.Object object) Coerces the passed object to a numeric value.
static java.lang.String	toString(java.lang.Object object) Converts the passed object to a String.

Methods inherited from class java.lang.Object

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

Field Detail

PRIMITIVE_CLASSES

public static final java.util.Set<java.lang.Class<?>> PRIMITIVE_CLASSES

A Set that stores all the supported primitive classes.

Method Detail

isPrimitive

public static boolean isPrimitive(java.lang.Object object)

Checks if the provided object is an instance of a primitive class.

Parameters:

object - the Object to check

Returns:

true if the object is a primitive, false otherwise

resolveProperty

public static java.lang.Object resolveProperty(java.lang.Object target,
                                               java.lang.Object property)

Given the target object, this method attempts to resolve and return the value of the passed property.

The property can be either an index or a name:

• index: the property is considered an index if its value is an integer number and in this case the target will be assumed to be either an array or it will be converted to a Collection; a fallback to Map will be made in case the previous two attempts failed
• name: the property will be converted to a String (see toString(Object)); the target will be assumed to be either a Map or an object; if the Map attempt fails, the property will be used to check if the target has a publicly accessible field with this name or a publicly accessible method with no parameters with this name or a combination of the "get" or "is" prefixes plus the capitalised name (see invokeBeanMethod(Object, String))

Parameters:

target - the target object

property - the property to be resolved

Returns:

the value of the property or null

toBoolean

public static boolean toBoolean(java.lang.Object object)

Converts the given object to a boolean value, applying the following rules:

• if the object is null the returned value is false
• if the object is a Number the method will return false only if the number's value is 0
• if the String representation of the object is equal irrespective of its casing to "true", the method will return true
• if the object is a Collection or a Map, the method will return true only if the collection / map is not empty
• if the object is an array, the method will return true only if the array is not empty

Parameters:

object - the target object

Returns:

the boolean representation of the object according to the conversion rules

toNumber

public static java.lang.Number toNumber(java.lang.Object object)

Coerces the passed object to a numeric value. If the passed value is a String the conversion rules are those of NumberUtils.createNumber(String).

Parameters:

object - the target object

Returns:

the numeric representation if one can be determined or null

See Also:

NumberUtils.createNumber(String)

toString

public static java.lang.String toString(java.lang.Object object)

Converts the passed object to a String. The following rules apply:

• if the object is null an empty string will be returned
• if the object is an instance of a String the object itself will be returned
• if the object is a primitive (see isPrimitive(Object)), its String representation will be returned
• if the object is an Enum its name will be returned (see Enum.name())
• otherwise an attempt to convert the object to a Collection will be made and then the output of collectionToString(Collection) will be returned

Parameters:

object - the target object

Returns:

the string representation of the object or an empty string

toCollection

public static java.util.Collection<java.lang.Object> toCollection(java.lang.Object object)

Forces the conversion of the passed object to a collection, according to the following rules:

• if the object is null an empty collection will be returned
• if the object is an array a list transformation of the array will be returned
• if the object is a Collection the object itself will be returned
• if the object is an instance of a Map the map's key set will be returned (see Map.keySet())
• if the object is an instance of an Enumeration a list transformation will be returned
• if the object is an instance of an Iterator or Iterable the result of fromIterator(Iterator) will be returned
• if the object is an instance of a String or Number a Collection containing only this object will be returned
• any other case not covered by the previous rules will result in an empty Collection

Parameters:

object - the target object

Returns:

the collection representation of the object

collectionToString

public static java.lang.String collectionToString(java.util.Collection<?> collection)

Converts the passed collection to a comma separated values String representation.

Parameters:

collection - the collection to be converted to CSV

Returns:

the CSV; if the collection is empty then an empty string will be returned

fromIterator

public static java.util.Collection<java.lang.Object> fromIterator(java.util.Iterator<java.lang.Object> iterator)

Given an iterator, this method will return a Collection.

Parameters:

iterator - the iterator to be transformed into a collection

Returns:

a collection with the iterator's elements

getIndex

public static java.lang.Object getIndex(java.lang.Object object,
                                        int index)

Given an indexable object (i.e. an array or a collection), this method will return the value available at the index position.

Parameters:

object - the indexable object

index - the index

Returns:

the value stored at the index or null

getField

public static java.lang.Object getField(java.lang.Object object,
                                        java.lang.String fieldName)

Given an object, this method will return the value of the public field identified by fieldName.

Parameters:

object - the target object

fieldName - the name of the field

Returns:

the value of the field or null if the field was not found

invokeBeanMethod

public static java.lang.Object invokeBeanMethod(java.lang.Object object,
                                                java.lang.String methodName)

Given a bean object, this method will invoke the public method without parameters identified by methodName and return the invocation's result.

Parameters:

object - the target object

methodName - the name of the public method without parameters to invoke

Returns:

the invocation's result or null if such a method cannot be found

findBeanMethod

public static java.lang.reflect.Method findBeanMethod(java.lang.Class<?> cls,
                                                      java.lang.String baseName)

Given a bean class and a base method name, this method will try to find a public method without parameters that is named:

1. baseName
2. get + BaseName
3. is + BaseName

Parameters:

cls - the class into which to search for the method

baseName - the base method name

Returns:

a method that matches the criteria or null

isMethodAllowed

public static boolean isMethodAllowed(java.lang.reflect.Method method)

Returns true if the method is not one of the Object's class declared methods, with the exception of Object.toString().

Parameters:

method - the method to check

Returns:

true if the method is not one of the Object's class declared methods, with the exception of Object.toString(), false otherwise