org.robolectric.util

Class ReflectionHelpers

java.lang.Object

org.robolectric.util.ReflectionHelpers

public class ReflectionHelpers
extends Object

Collection of helper methods for calling methods and accessing fields reflectively.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ReflectionHelpers.ClassParameter<V> Typed parameter used with reflective method calls.
static class	ReflectionHelpers.StringParameter<V> String parameter used with reflective method calls.

Constructor Summary

Constructors

Constructor and Description
ReflectionHelpers()

Method Summary

Modifier and Type	Method and Description
static <R> R	callConstructor(Class<? extends R> clazz, ReflectionHelpers.ClassParameter<?>... classParameters) Reflectively call the constructor of an object.
static <R> R	callInstanceMethod(Class<?> cl, Object instance, String methodName, ReflectionHelpers.ClassParameter<?>... classParameters) Reflectively call an instance method on an object on a specific class.
static <R> R	callInstanceMethod(Object instance, String methodName, ReflectionHelpers.ClassParameter<?>... classParameters) Reflectively call an instance method on an object.
static <R> R	callStaticMethod(Class<?> clazz, String methodName, ReflectionHelpers.ClassParameter<?>... classParameters) Reflectively call a static method on a class.
static <T> T	createDeepProxy(Class<T> clazz) Create a proxy for the given class which returns other deep proxies from all it’s methods.
static <T> T	createDelegatingProxy(Class<T> clazz, Object delegate)
static <T> T	createNullProxy(Class<T> clazz)
static <A extends Annotation> A	defaultsFor(Class<A> annotation)
static Object	defaultValueForType(String returnType)
static <R> R	getField(Object object, String fieldName) Reflectively get the value of a field.
static <R> R	getStaticField(Class<?> clazz, String fieldName) Reflectively get the value of a static field.
static <R> R	getStaticField(Field field) Reflectively get the value of a static field.
static Class<?>	loadClass(ClassLoader classLoader, String fullyQualifiedClassName) Load a class.
static <T> T	newInstance(Class<T> cl) Create a new instance of a class
static void	setField(Class<?> type, Object object, String fieldName, Object fieldNewValue) Reflectively set the value of a field.
static void	setField(Object object, String fieldName, Object fieldNewValue) Reflectively set the value of a field.
static void	setStaticField(Class<?> clazz, String fieldName, Object fieldNewValue) Reflectively set the value of a static field.
static void	setStaticField(Field field, Object fieldNewValue) Reflectively set the value of a static field.

Methods inherited from class java.lang.Object

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

Constructor Detail

ReflectionHelpers

public ReflectionHelpers()

Method Detail

createNullProxy

public static <T> T createNullProxy(Class<T> clazz)

createDeepProxy

public static <T> T createDeepProxy(Class<T> clazz)

Create a proxy for the given class which returns other deep proxies from all it’s methods.

The returned object will be an instance of the given class, but all methods will return either the “default” value for primitives, or another deep proxy for non-primitive types.

This should be used rarely, for cases where we need to create deep proxies in order not to crash. The inner proxies are impossible to configure, so there is no way to create meaningful behavior from a deep proxy. It serves mainly to prevent Null Pointer Exceptions.

Parameters:

clazz - the class to provide a proxy instance of.

Returns:

a new “Deep Proxy” instance of the given class.

createDelegatingProxy

public static <T> T createDelegatingProxy(Class<T> clazz,
                                          Object delegate)

defaultsFor

public static <A extends Annotation> A defaultsFor(Class<A> annotation)

getField

public static <R> R getField(Object object,
                             String fieldName)

Reflectively get the value of a field.

Type Parameters:

R - The return type.

Parameters:

object - Target object.

fieldName - The field name.

Returns:

Value of the field on the object.

setField

public static void setField(Object object,
                            String fieldName,
                            Object fieldNewValue)

Reflectively set the value of a field.

Parameters:

object - Target object.

fieldName - The field name.

fieldNewValue - New value.

setField

public static void setField(Class<?> type,
                            Object object,
                            String fieldName,
                            Object fieldNewValue)

Reflectively set the value of a field.

Parameters:

type - Target type.

object - Target object.

fieldName - The field name.

fieldNewValue - New value.

getStaticField

public static <R> R getStaticField(Field field)

Reflectively get the value of a static field.

Type Parameters:

R - The return type.

Parameters:

field - Field object.

Returns:

Value of the field.

getStaticField

public static <R> R getStaticField(Class<?> clazz,
                                   String fieldName)

Reflectively get the value of a static field.

Type Parameters:

R - The return type.

Parameters:

clazz - Target class.

fieldName - The field name.

Returns:

Value of the field.

setStaticField

public static void setStaticField(Field field,
                                  Object fieldNewValue)

Reflectively set the value of a static field.

Parameters:

field - Field object.

fieldNewValue - The new value.

setStaticField

public static void setStaticField(Class<?> clazz,
                                  String fieldName,
                                  Object fieldNewValue)

Reflectively set the value of a static field.

Parameters:

clazz - Target class.

fieldName - The field name.

fieldNewValue - The new value.

callInstanceMethod

public static <R> R callInstanceMethod(Object instance,
                                       String methodName,
                                       ReflectionHelpers.ClassParameter<?>... classParameters)

Reflectively call an instance method on an object.

Type Parameters:

R - The return type.

Parameters:

instance - Target object.

methodName - The method name to call.

classParameters - Array of parameter types and values.

Returns:

The return value of the method.

callInstanceMethod

public static <R> R callInstanceMethod(Class<?> cl,
                                       Object instance,
                                       String methodName,
                                       ReflectionHelpers.ClassParameter<?>... classParameters)

Reflectively call an instance method on an object on a specific class.

Type Parameters:

R - The return type.

Parameters:

cl - The class.

instance - Target object.

methodName - The method name to call.

classParameters - Array of parameter types and values.

Returns:

The return value of the method.

callStaticMethod

public static <R> R callStaticMethod(Class<?> clazz,
                                     String methodName,
                                     ReflectionHelpers.ClassParameter<?>... classParameters)

Reflectively call a static method on a class.

Type Parameters:

R - The return type.

Parameters:

clazz - Target class.

methodName - The method name to call.

classParameters - Array of parameter types and values.

Returns:

The return value of the method.

loadClass

public static Class<?> loadClass(ClassLoader classLoader,
                                 String fullyQualifiedClassName)

Load a class.

Parameters:

classLoader - The class loader.

fullyQualifiedClassName - The fully qualified class name.

Returns:

The class object.

newInstance

public static <T> T newInstance(Class<T> cl)

Create a new instance of a class

Type Parameters:

T - The class type.

Parameters:

cl - The class object.

Returns:

New class instance.

callConstructor

public static <R> R callConstructor(Class<? extends R> clazz,
                                    ReflectionHelpers.ClassParameter<?>... classParameters)

Reflectively call the constructor of an object.

Type Parameters:

R - The return type.

Parameters:

clazz - Target class.

classParameters - Array of parameter types and values.

Returns:

The return value of the method.

defaultValueForType

public static Object defaultValueForType(String returnType)