org.assertj.core.util.introspection

Class FieldSupport

java.lang.Object

org.assertj.core.util.introspection.FieldSupport

public class FieldSupport
extends Object

Utility methods for fields access.

Author:

Joel Costigliola

Method Summary

Methods

Modifier and Type	Method and Description
<T> T	fieldValue(String fieldName, Class<T> clazz, Object target) Return the value of field from a target object.
<T> T	fieldValueOf(String fieldName, Class<T> clazz, Object target) Returns the value of the given field name given target.
static <T> T	fieldValueOf(String fieldName, Object target, Class<T> clazz) Static variant of fieldValue(String, Class, Object) for syntactic sugar.
<T> List<T>	fieldValues(String fieldName, Class<T> fieldClass, Iterable<?> target) Returns a List containing the values of the given field name, from the elements of the given Iterable.
<T> List<T>	fieldValues(String fieldName, Class<T> fieldClass, Object[] target) Returns a List containing the values of the given field name, from the elements of the given Iterable.
List<Object>	fieldValues(String fieldName, Iterable<?> target)
List<Object>	fieldValues(String fieldName, Object[] target)
static FieldSupport	instance() Returns the singleton instance of this class.

Methods inherited from class java.lang.Object

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

Method Detail

instance

public static FieldSupport instance()

Returns the singleton instance of this class.

Returns:

the singleton instance of this class.

fieldValues

public <T> List<T> fieldValues(String fieldName,
                      Class<T> fieldClass,
                      Iterable<?> target)

Returns a List containing the values of the given field name, from the elements of the given Iterable. If the given Iterable is empty or null, this method will return an empty List. This method supports nested fields (e.g. "address.street.number").

Parameters:

fieldName - the name of the field. It may be a nested field. It is left to the clients to validate for null or empty.

fieldClass - the expected type of the given field.

target - the given Iterable.

Returns:

an Iterable containing the values of the given field name, from the elements of the given Iterable.

Throws:

IntrospectionError - if an element in the given Iterable does not have a field with a matching name.

fieldValues

public List<Object> fieldValues(String fieldName,
                       Iterable<?> target)

fieldValues

public <T> List<T> fieldValues(String fieldName,
                      Class<T> fieldClass,
                      Object[] target)

Returns a List containing the values of the given field name, from the elements of the given Iterable. If the given Iterable is empty or null, this method will return an empty List. This method supports nested fields (e.g. "address.street.number").

Parameters:

fieldName - the name of the field. It may be a nested field. It is left to the clients to validate for null or empty.

fieldClass - the expected type of the given field.

target - the given Iterable.

Returns:

an Iterable containing the values of the given field name, from the elements of the given Iterable.

Throws:

IntrospectionError - if an element in the given Iterable does not have a field with a matching name.

fieldValues

public List<Object> fieldValues(String fieldName,
                       Object[] target)

fieldValueOf

public static <T> T fieldValueOf(String fieldName,
                 Object target,
                 Class<T> clazz)

Static variant of fieldValue(String, Class, Object) for syntactic sugar.

Parameters:

fieldName - the name of the field. It may be a nested field. It is left to the clients to validate for null or empty.

target - the given object

Returns:

a the values of the given field name

Throws:

IntrospectionError - if the given target does not have a field with a matching name.

fieldValue

public <T> T fieldValue(String fieldName,
               Class<T> clazz,
               Object target)

Return the value of field from a target object.

Parameters:

fieldName - the name of the field. It may be a nested field. It is left to the clients to validate for null or empty.

target - the given object

clazz - type of field

Returns:

a the values of the given field name

Throws:

IntrospectionError - if the given target does not have a field with a matching name.

fieldValueOf

public <T> T fieldValueOf(String fieldName,
                 Class<T> clazz,
                 Object target)

Returns the value of the given field name given target. If the given object is null, this method will return null.
This method supports nested fields (e.g. "address.street.number").

Parameters:

fieldName - the name of the field. It may be a nested field. It is left to the clients to validate for null or empty.

clazz - the class of field.

target - the given Object to extract field from.

Returns:

the value of the given field name given target.

Throws:

IntrospectionError - if target object does not have a field with a matching name.