com.haulmont.bali.util

Class ReflectionHelper

java.lang.Object

com.haulmont.bali.util.ReflectionHelper

public final class ReflectionHelper
extends java.lang.Object

Utility class to simplify work with Java reflection.

Method Summary

Modifier and Type	Method and Description
static java.lang.reflect.Method	findMethod(java.lang.Class c, java.lang.String name, java.lang.Object... params) Searches for a method by its name and arguments.
static <T> java.lang.Class<T>	getClass(java.lang.String name) Load class by name, wrapping a ClassNotFoundException into unchecked exception.
static java.lang.Class[]	getParamTypes(java.lang.Object... params) Constructs an array of argument types from an array of actual values.
static <T> T	invokeMethod(java.lang.Object obj, java.lang.String name, java.lang.Object... params) Invokes a method by reflection.
static java.lang.Class<?>	loadClass(java.lang.String name) Load class by name.
static <T> T	newInstance(java.lang.Class<T> cls, java.lang.Object... params) Instantiates an object by appropriate constructor.

Methods inherited from class java.lang.Object

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

Method Detail

loadClass

public static java.lang.Class<?> loadClass(java.lang.String name)
                                    throws java.lang.ClassNotFoundException

Load class by name.

Parameters:

name - class FQN or primitive type name

Returns:

class instance

Throws:

java.lang.ClassNotFoundException - if not found

getClass

public static <T> java.lang.Class<T> getClass(java.lang.String name)

Load class by name, wrapping a ClassNotFoundException into unchecked exception.

Parameters:

name - class FQN

Returns:

class instance

newInstance

public static <T> T newInstance(java.lang.Class<T> cls,
                                java.lang.Object... params)
                         throws java.lang.NoSuchMethodException

Instantiates an object by appropriate constructor.

Parameters:

cls - class

params - constructor arguments

Returns:

created object instance

Throws:

java.lang.NoSuchMethodException - if the class has no constructor matching the given arguments

findMethod

@Nullable
public static java.lang.reflect.Method findMethod(java.lang.Class c,
                                                            java.lang.String name,
                                                            java.lang.Object... params)

Searches for a method by its name and arguments.

Parameters:

c - class

name - method name

params - method arguments

Returns:

method reference or null if a suitable method not found

invokeMethod

public static <T> T invokeMethod(java.lang.Object obj,
                                 java.lang.String name,
                                 java.lang.Object... params)
                          throws java.lang.NoSuchMethodException

Invokes a method by reflection.

Parameters:

obj - object instance

name - method name

params - method arguments

Returns:

method result

Throws:

java.lang.NoSuchMethodException - if a suitable method not found

getParamTypes

public static java.lang.Class[] getParamTypes(java.lang.Object... params)

Constructs an array of argument types from an array of actual values. Values can not contain nulls.

Parameters:

params - arguments

Returns:

the array of argument types