Package com.palantir.ptoss.util

Class Reflections

java.lang.Object

com.palantir.ptoss.util.Reflections

public class Reflections
extends Object

A collection of utility methods and classes to handle all the of the Java Reflection calls need to wire and fire bindings.

See Also:

• java.lang.reflect

Field Summary

Fields

Modifier and Type	Field	Description
static final com.google.common.base.Function<Field,String>	FIELD_TO_CONTAINING_CLASS_NAME	Function that maps a Field to the simple name for the containing class.
static final com.google.common.base.Function<Field,String>	FIELD_TO_NAME	Function that maps a Field to its string name.
static final com.google.common.base.Predicate<Field>	IS_FIELD_FINAL	Predicate to determine whether or not the specified field is final.

Constructor Summary

Constructors

Constructor	Description
Reflections()

Method Summary

Modifier and Type	Method	Description
static Object	evalEnum(Class<?> enumType, String value)	Looks up an Enum value by its String name.
static List<Field>	getAnnotatedFields(Class<?> klass, Class<? extends Annotation> annotation)	Returns the list of fields on this class annotated with the passed Annotation
static List<Field>	getAnnotatedFieldsForClassHierarchy(Class<?> klass, Class<? extends Annotation> annotation)	Returns the list of fields on this class or any of its ancestors annotated with the passed Annotation.
static Field	getFieldByName(Class<?> klass, String fieldName)	Find a Field based on the field name.
static <T> T	getFieldObject(Object object, Field field, Class<T> klass)	Given an Object and a Field of a known Class type, get the field.
static List<Field>	getFieldsOfType(Class<?> klass, Class<?> targetClass)	Gets all fields from a given class that are assignable from the target class.
static List<Field>	getFieldsOfTypeForClassHierarchy(Class<?> klass, Class<?> targetClass)	Gets all fields assignable from targetClass in the passed class's type hierarchy.
static List<ObjectFieldMethod>	getParameterlessMethodsForClassHierarchy(Object object)	Returns all methods in the passed object's class hierarchy that do no not take parameters
static <F, T> com.google.common.base.Function<F,T>	getterFunction(Class<F> klass, Class<T> returnType, String getter)	Returns a Function that will read values from the named field from a passed object.
static List<Class<?>>	getTypesOfType(Class<?> klass, Class<?> targetClass)	Gets all inner classes from a given class that are assignable from the target class.
static List<Class<?>>	getTypesOfTypeForClassHierarchy(Class<?> klass, Class<?> targetClass)	Gets all inner classes assignable from targetClass in the passed class's type hierarchy.
static boolean	isClassAnnotatedForClassHierarchy(Object object, Class<? extends Annotation> annotation)	Checks whether or not the specified Annotation exists in the passed Object's class hierarchy.
static boolean	isFieldFinal(Field field)	Returns whether or not the given Field is final.
static boolean	isFieldStatic(Field field)	Returns whether or not the given Field is static.
static boolean	isMethodPublic(Method method)	Returns whether or not the given Method is public.
static void	visitClassHierarchy(Class<?> klass, Visitor<Class<?>> visitor)	Starting at the bottom of a class hierarchy, visit all classes (ancestors) in the hierarchy.

Methods inherited from class java.lang.Object

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

Field Details

FIELD_TO_CONTAINING_CLASS_NAME

public static final com.google.common.base.Function<Field,String> FIELD_TO_CONTAINING_CLASS_NAME

Function that maps a Field to the simple name for the containing class.

See Also:

• Class.getSimpleName()

FIELD_TO_NAME

public static final com.google.common.base.Function<Field,String> FIELD_TO_NAME

Function that maps a Field to its string name.

See Also:

• Field.getName()

IS_FIELD_FINAL

public static final com.google.common.base.Predicate<Field> IS_FIELD_FINAL

Predicate to determine whether or not the specified field is final.

See Also:

• Modifier.isFinal(int)

Constructor Details

Reflections

public Reflections()

Method Details

visitClassHierarchy

public static void visitClassHierarchy(Class<?> klass,
 Visitor<Class<?>> visitor)

Starting at the bottom of a class hierarchy, visit all classes (ancestors) in the hierarchy. Does not visit interfaces.

Parameters:

klass - Class to use as the bottom of the class hierarchy

visitor - Visitor object

getFieldObject

public static <T> T getFieldObject(Object object,
 Field field,
 Class<T> klass)

Given an Object and a Field of a known Class type, get the field. This will return the value of the field regardless of visibility modifiers (i.e., it will return the value of private fields.)

isFieldFinal

public static boolean isFieldFinal(Field field)

Returns whether or not the given Field is final.

isFieldStatic

public static boolean isFieldStatic(Field field)

Returns whether or not the given Field is static.

isMethodPublic

public static boolean isMethodPublic(Method method)

Returns whether or not the given Method is public.

getFieldByName

public static Field getFieldByName(Class<?> klass,
 String fieldName)

Find a Field based on the field name. Will return private fields but will not look in superclasses.

Returns:

null if there is no field found

getTypesOfType

public static List<Class<?>> getTypesOfType(Class<?> klass,
 Class<?> targetClass)

Gets all inner classes from a given class that are assignable from the target class.

Parameters:

klass - type to query for inner-classes.

targetClass - interface or class that inner classes must be assignable from to be returned.

Returns:

all inner classes in klass that are assignable from targetClass

See Also:

• Class.isAssignableFrom(Class)
• Class.getDeclaredClasses()

getTypesOfTypeForClassHierarchy

public static List<Class<?>> getTypesOfTypeForClassHierarchy(Class<?> klass,
 Class<?> targetClass)

Gets all inner classes assignable from targetClass in the passed class's type hierarchy.

Parameters:

klass - starting point in the type stack to query for inner classes.

targetClass - looks for inner classes that are assignable from this type.

Returns:

all inner classes in klass's type hierarchy assignable from targetclass

See Also:

• Class.isAssignableFrom(Class)
• Class.getDeclaredClasses()
• getTypesOfType(Class, Class)

getFieldsOfType

public static List<Field> getFieldsOfType(Class<?> klass,
 Class<?> targetClass)

Gets all fields from a given class that are assignable from the target class.

Parameters:

klass - type to query for fields.

targetClass - interface or class that fields must be assignable from to be returned.

Returns:

all fields in klass that are assignable from targetClass

See Also:

• Class.isAssignableFrom(Class)
• Class.getDeclaredFields()

getFieldsOfTypeForClassHierarchy

public static List<Field> getFieldsOfTypeForClassHierarchy(Class<?> klass,
 Class<?> targetClass)

Gets all fields assignable from targetClass in the passed class's type hierarchy.

Parameters:

klass - starting point in the type stack to query for fields of the specified type.

targetClass - looks for fields that are assignable from this type.

Returns:

all fields declared by classes in klass's type hierarchy assignable from targetclass

See Also:

• Class.isAssignableFrom(Class)
• Class.getDeclaredClasses()
• getTypesOfType(Class, Class)

evalEnum

public static Object evalEnum(Class<?> enumType,
 String value)

Looks up an Enum value by its String name.

Parameters:

enumType - Enum class to query.

value - String name for the Enum value.

Returns:

the actual Enum value specified by the passed name.

See Also:

• Enum.valueOf(Class, String)

isClassAnnotatedForClassHierarchy

public static boolean isClassAnnotatedForClassHierarchy(Object object,
 Class<? extends Annotation> annotation)

Checks whether or not the specified Annotation exists in the passed Object's class hierarchy.

Parameters:

object - object to check

annotation - annotation to look for

Returns:

true is a class in this passed object's type hierarchy is annotated with the passed Annotation

getAnnotatedFields

public static List<Field> getAnnotatedFields(Class<?> klass,
 Class<? extends Annotation> annotation)

Returns the list of fields on this class annotated with the passed Annotation

Parameters:

klass - checks the Fields on this class

annotation - looks for this Annotation

Returns:

list of all Fields that are annotated with the specified Annotation

getAnnotatedFieldsForClassHierarchy

public static List<Field> getAnnotatedFieldsForClassHierarchy(Class<?> klass,
 Class<? extends Annotation> annotation)

Returns the list of fields on this class or any of its ancestors annotated with the passed Annotation.

Parameters:

klass - checks the Fields on this class and its ancestors

annotation - looks for this Annotation

Returns:

list of all Fields that are annotated with the specified Annotation

getParameterlessMethodsForClassHierarchy

public static List<ObjectFieldMethod> getParameterlessMethodsForClassHierarchy(Object object)

Returns all methods in the passed object's class hierarchy that do no not take parameters

Parameters:

object - object to query for parameterless methods

Returns:

a list ObjectFieldMethod tuples mapping the parameterless methods to the passed object.

getterFunction

public static <F,
T>
com.google.common.base.Function<F,T> getterFunction(Class<F> klass,
 Class<T> returnType,
 String getter)

Returns a Function that will read values from the named field from a passed object.

Parameters:

klass - type to read values from

returnType - return type of read field

getter - name of the field

Returns:

a Function object that, when applied to an instance of klass, returns the of type returnType that resides in field getter