nonapi.io.github.classgraph.reflection

Class ReflectionUtils

java.lang.Object

nonapi.io.github.classgraph.reflection.ReflectionUtils

public final class ReflectionUtils
extends java.lang.Object

Reflection utility methods that can be used by ClassLoaderHandlers.

Field Summary

Fields

Modifier and Type	Field and Description
static nonapi.io.github.classgraph.reflection.ReflectionDriver	reflectionDriver The reflection driver to use.

Method Summary

Modifier and Type	Method and Description
static java.lang.Class<?>	classForNameOrNull(java.lang.String className) Call Class.forName(className), but return null if any exception is thrown.
static <T> T	doPrivileged(java.util.concurrent.Callable<T> callable) Call a method in the AccessController.doPrivileged(PrivilegedAction) context, using reflection, if possible (AccessController is deprecated in JDK 17).
static java.lang.Object	getFieldVal(boolean throwException, java.lang.Object obj, java.lang.reflect.Field field) Get the value of the field in the class of the given object or any of its superclasses.
static java.lang.Object	getFieldVal(boolean throwException, java.lang.Object obj, java.lang.String fieldName) Get the value of the named field in the class of the given object or any of its superclasses.
static java.lang.Object	getStaticFieldVal(boolean throwException, java.lang.Class<?> cls, java.lang.String fieldName) Get the value of the named static field in the given class or any of its superclasses.
static java.lang.Object	invokeMethod(boolean throwException, java.lang.Object obj, java.lang.String methodName) Invoke the named method in the given object or its superclasses.
static java.lang.Object	invokeMethod(boolean throwException, java.lang.Object obj, java.lang.String methodName, java.lang.Class<?> argType, java.lang.Object param) Invoke the named method in the given object or its superclasses.
static java.lang.Object	invokeStaticMethod(boolean throwException, java.lang.Class<?> cls, java.lang.String methodName) Invoke the named static method.
static java.lang.Object	invokeStaticMethod(boolean throwException, java.lang.Class<?> cls, java.lang.String methodName, java.lang.Class<?> argType, java.lang.Object param) Invoke the named static method.
static void	loadReflectionDriver() Call this if you change the value of ClassGraph.CIRCUMVENT_ENCAPSULATION.

Methods inherited from class java.lang.Object

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

Field Detail

reflectionDriver

public static nonapi.io.github.classgraph.reflection.ReflectionDriver reflectionDriver

The reflection driver to use.

Method Detail

loadReflectionDriver

public static void loadReflectionDriver()

Call this if you change the value of ClassGraph.CIRCUMVENT_ENCAPSULATION.

getFieldVal

public static java.lang.Object getFieldVal(boolean throwException,
                                           java.lang.Object obj,
                                           java.lang.reflect.Field field)
                                    throws java.lang.IllegalArgumentException

Get the value of the field in the class of the given object or any of its superclasses. If an exception is thrown while trying to read the field, and throwException is true, then IllegalArgumentException is thrown wrapping the cause, otherwise this will return null. If passed a null object, returns null unless throwException is true, then throws IllegalArgumentException.

Parameters:

throwException - If true, throw an exception if the field value could not be read.

obj - The object.

field - The field.

Returns:

The field value.

Throws:

java.lang.IllegalArgumentException - If the field value could not be read.

getFieldVal

public static java.lang.Object getFieldVal(boolean throwException,
                                           java.lang.Object obj,
                                           java.lang.String fieldName)
                                    throws java.lang.IllegalArgumentException

Get the value of the named field in the class of the given object or any of its superclasses. If an exception is thrown while trying to read the field, and throwException is true, then IllegalArgumentException is thrown wrapping the cause, otherwise this will return null. If passed a null object, returns null unless throwException is true, then throws IllegalArgumentException.

Parameters:

throwException - If true, throw an exception if the field value could not be read.

obj - The object.

fieldName - The field name.

Returns:

The field value.

Throws:

java.lang.IllegalArgumentException - If the field value could not be read.

getStaticFieldVal

public static java.lang.Object getStaticFieldVal(boolean throwException,
                                                 java.lang.Class<?> cls,
                                                 java.lang.String fieldName)
                                          throws java.lang.IllegalArgumentException

Get the value of the named static field in the given class or any of its superclasses. If an exception is thrown while trying to read the field value, and throwException is true, then IllegalArgumentException is thrown wrapping the cause, otherwise this will return null. If passed a null class reference, returns null unless throwException is true, then throws IllegalArgumentException.

Parameters:

throwException - If true, throw an exception if the field value could not be read.

cls - The class.

fieldName - The field name.

Returns:

The field value.

Throws:

java.lang.IllegalArgumentException - If the field value could not be read.

invokeMethod

public static java.lang.Object invokeMethod(boolean throwException,
                                            java.lang.Object obj,
                                            java.lang.String methodName)
                                     throws java.lang.IllegalArgumentException

Invoke the named method in the given object or its superclasses. If an exception is thrown while trying to call the method, and throwException is true, then IllegalArgumentException is thrown wrapping the cause, otherwise this will return null. If passed a null object, returns null unless throwException is true, then throws IllegalArgumentException.

Parameters:

throwException - If true, throw an exception if the field value could not be read.

obj - The object.

methodName - The method name.

Returns:

The result of the method invocation.

Throws:

java.lang.IllegalArgumentException - If the method could not be invoked.

invokeMethod

public static java.lang.Object invokeMethod(boolean throwException,
                                            java.lang.Object obj,
                                            java.lang.String methodName,
                                            java.lang.Class<?> argType,
                                            java.lang.Object param)
                                     throws java.lang.IllegalArgumentException

Invoke the named method in the given object or its superclasses. If an exception is thrown while trying to call the method, and throwException is true, then IllegalArgumentException is thrown wrapping the cause, otherwise this will return null. If passed a null object, returns null unless throwException is true, then throws IllegalArgumentException.

Parameters:

throwException - Whether to throw an exception on failure.

obj - The object.

methodName - The method name.

argType - The type of the method argument.

param - The parameter value to use when invoking the method.

Returns:

The result of the method invocation.

Throws:

java.lang.IllegalArgumentException - If the method could not be invoked.

invokeStaticMethod

public static java.lang.Object invokeStaticMethod(boolean throwException,
                                                  java.lang.Class<?> cls,
                                                  java.lang.String methodName)
                                           throws java.lang.IllegalArgumentException

Invoke the named static method. If an exception is thrown while trying to call the method, and throwException is true, then IllegalArgumentException is thrown wrapping the cause, otherwise this will return null. If passed a null class reference, returns null unless throwException is true, then throws IllegalArgumentException.

Parameters:

throwException - Whether to throw an exception on failure.

cls - The class.

methodName - The method name.

Returns:

The result of the method invocation.

Throws:

java.lang.IllegalArgumentException - If the method could not be invoked.

invokeStaticMethod

public static java.lang.Object invokeStaticMethod(boolean throwException,
                                                  java.lang.Class<?> cls,
                                                  java.lang.String methodName,
                                                  java.lang.Class<?> argType,
                                                  java.lang.Object param)
                                           throws java.lang.IllegalArgumentException

Invoke the named static method. If an exception is thrown while trying to call the method, and throwException is true, then IllegalArgumentException is thrown wrapping the cause, otherwise this will return null. If passed a null class reference, returns null unless throwException is true, then throws IllegalArgumentException.

Parameters:

throwException - Whether to throw an exception on failure.

cls - The class.

methodName - The method name.

argType - The type of the method argument.

param - The parameter value to use when invoking the method.

Returns:

The result of the method invocation.

Throws:

java.lang.IllegalArgumentException - If the method could not be invoked.

classForNameOrNull

public static java.lang.Class<?> classForNameOrNull(java.lang.String className)

Call Class.forName(className), but return null if any exception is thrown.

Parameters:

className - The class name to load.

Returns:

The class of the requested name, or null if an exception was thrown while trying to load the class.

doPrivileged

public static <T> T doPrivileged(java.util.concurrent.Callable<T> callable)
                          throws java.lang.Throwable

Call a method in the AccessController.doPrivileged(PrivilegedAction) context, using reflection, if possible (AccessController is deprecated in JDK 17).

Throws:

java.lang.Throwable