/*
* @(#)Methods.java
*
* Copyright (c) 1996-2010 The authors and contributors of JHotDraw.
* You may not use, copy or modify this file, except in compliance with the
* accompanying license terms.
*/
package org.jhotdraw.util;
import java.lang.reflect.*;
/**
* Methods contains convenience methods for method invocations using
* java.lang.reflect.
*
* @author Werner Randelshofer
* @version $Id$
*/
@SuppressWarnings("unchecked")
public class Methods {
/**
* Prevent instance creation.
*/
private Methods() {
}
/**
* Invokes the specified accessible parameterless method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
* @return The return value of the method.
* @return NoSuchMethodException if the method does not exist or is not
* accessible.
*/
public static Object invoke(Object obj, String methodName)
throws NoSuchMethodException {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[0]);
Object result = method.invoke(obj, new Object[0]);
return result;
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified accessible method with a string parameter if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
* @param stringParameter The String parameter
* @return The return value of the method or METHOD_NOT_FOUND.
* @return NoSuchMethodException if the method does not exist or is not accessible.
*/
public static Object invoke(Object obj, String methodName, String stringParameter)
throws NoSuchMethodException {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[] { String.class });
Object result = method.invoke(obj, new Object[] { stringParameter });
return result;
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified accessible parameterless method if it exists.
*
* @param clazz The class on which to invoke the method.
* @param methodName The name of the method.
* @return The return value of the method or METHOD_NOT_FOUND.
* @return NoSuchMethodException if the method does not exist or is not accessible.
*/
public static Object invokeStatic(Class<?> clazz, String methodName)
throws NoSuchMethodException {
try {
Method method = clazz.getMethod(methodName, new Class<?>[0]);
Object result = method.invoke(null, new Object[0]);
return result;
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified accessible parameterless method if it exists.
*
* @param clazz The class on which to invoke the method.
* @param methodName The name of the method.
* @return The return value of the method.
* @return NoSuchMethodException if the method does not exist or is not accessible.
*/
public static Object invokeStatic(String clazz, String methodName)
throws NoSuchMethodException {
try {
return invokeStatic(Class.forName(clazz), methodName);
} catch (ClassNotFoundException e) {
throw new NoSuchMethodException("class "+clazz+" not found");
}
}
/**
* Invokes the specified parameterless method if it exists.
*
* @param clazz The class on which to invoke the method.
* @param methodName The name of the method.
* @param type The parameter type.
* @param value The parameter value.
* @return The return value of the method.
* @return NoSuchMethodException if the method does not exist or is not accessible.
*/
public static Object invokeStatic(Class<?> clazz, String methodName, Class<?> type, Object value)
throws NoSuchMethodException {
return invokeStatic(clazz,methodName,new Class<?>[]{type},new Object[]{value});
}
/**
* Invokes the specified parameterless method if it exists.
*
* @param clazz The class on which to invoke the method.
* @param methodName The name of the method.
* @param types The parameter types.
* @param values The parameter values.
* @return The return value of the method.
* @return NoSuchMethodException if the method does not exist or is not accessible.
*/
public static Object invokeStatic(Class<?> clazz, String methodName, Class<?>[] types, Object[] values)
throws NoSuchMethodException {
try {
Method method = clazz.getMethod(methodName, types);
Object result = method.invoke(null, values);
return result;
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified parameterless method if it exists.
*
* @param clazz The class on which to invoke the method.
* @param methodName The name of the method.
* @param types The parameter types.
* @param values The parameter values.
* @return The return value of the method.
* @return NoSuchMethodException if the method does not exist or is not accessible.
*/
public static Object invokeStatic(String clazz, String methodName,
Class<?>[] types, Object[] values)
throws NoSuchMethodException {
try {
return invokeStatic(Class.forName(clazz), methodName, types, values);
} catch (ClassNotFoundException e) {
throw new NoSuchMethodException("class "+clazz+" not found");
}
}
/**
* Invokes the specified parameterless method if it exists.
*
* @param clazz The class on which to invoke the method.
* @param methodName The name of the method.
* @param types The parameter types.
* @param values The parameter values.
* @param defaultValue The default value.
* @return The return value of the method or the default value if the method
* does not exist or is not accessible.
*/
public static Object invokeStatic(String clazz, String methodName,
Class<?>[] types, Object[] values, Object defaultValue) {
try {
return invokeStatic(Class.forName(clazz), methodName, types, values);
} catch (ClassNotFoundException | NoSuchMethodException e) {
return defaultValue;
}
}
/**
* Invokes the specified getter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
* @param defaultValue This value is returned, if the method does not exist.
* @return The value returned by the getter method or the default value.
*/
public static int invokeGetter(Object obj, String methodName, int defaultValue) {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[0]);
Object result = method.invoke(obj, new Object[0]);
return ((Integer) result);
} catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
return defaultValue;
}
}
/**
* Invokes the specified getter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
* @param defaultValue This value is returned, if the method does not exist.
* @return The value returned by the getter method or the default value.
*/
public static long invokeGetter(Object obj, String methodName, long defaultValue) {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[0]);
Object result = method.invoke(obj, new Object[0]);
return ((Long) result);
} catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
return defaultValue;
}
}
/**
* Invokes the specified getter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
* @param defaultValue This value is returned, if the method does not exist.
* @return The value returned by the getter method or the default value.
*/
public static boolean invokeGetter(Object obj, String methodName, boolean defaultValue) {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[0]);
Object result = method.invoke(obj, new Object[0]);
return ((Boolean) result);
} catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
return defaultValue;
}
}
/**
* Invokes the specified getter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
* @param defaultValue This value is returned, if the method does not exist.
* @return The value returned by the getter method or the default value.
*/
public static Object invokeGetter(Object obj, String methodName, Object defaultValue) {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[0]);
Object result = method.invoke(obj, new Object[0]);
return result;
} catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
return defaultValue;
}
}
/**
* Invokes the specified getter method if it exists.
*
* @param clazz The object on which to invoke the method.
* @param methodName The name of the method.
* @param defaultValue This value is returned, if the method does not exist.
* @return The value returned by the getter method or the default value.
*/
public static boolean invokeStaticGetter(Class<?> clazz, String methodName, boolean defaultValue) {
try {
Method method = clazz.getMethod(methodName, new Class<?>[0]);
Object result = method.invoke(null, new Object[0]);
return ((Boolean) result);
} catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
return defaultValue;
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static Object invoke(Object obj, String methodName, boolean newValue)
throws NoSuchMethodException {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[] { Boolean.TYPE} );
return method.invoke(obj, new Object[] { newValue});
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static Object invoke(Object obj, String methodName, int newValue)
throws NoSuchMethodException {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[] { Integer.TYPE} );
return method.invoke(obj, new Object[] { newValue});
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static Object invoke(Object obj, String methodName, float newValue)
throws NoSuchMethodException {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[] { Float.TYPE} );
return method.invoke(obj, new Object[] { newValue});
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static Object invoke(Object obj, String methodName, Class<?> clazz, Object newValue)
throws NoSuchMethodException {
try {
Method method = obj.getClass().getMethod(methodName, new Class<?>[] { clazz } );
return method.invoke(obj, new Object[] { newValue});
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
throw new InternalError(e.getMessage());
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static Object invoke(Object obj, String methodName, Class<?>[] clazz, Object... newValue)
throws NoSuchMethodException {
try {
Method method = obj.getClass().getMethod(methodName, clazz );
return method.invoke(obj, newValue);
} catch (IllegalAccessException e) {
throw new NoSuchMethodException(methodName+" is not accessible");
} catch (InvocationTargetException e) {
// The method is not supposed to throw exceptions
InternalError error = new InternalError(e.getMessage());
error.initCause((e.getCause() != null) ? e.getCause() : e);
throw error;
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static void invokeIfExists(Object obj, String methodName) {
try {
invoke(obj, methodName);
} catch (NoSuchMethodException e) {
// ignore
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static void invokeIfExists(Object obj, String methodName, float newValue) {
try {
invoke(obj, methodName, newValue);
} catch (NoSuchMethodException e) {
// ignore
}
}
/**
* Invokes the specified method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static void invokeIfExists(Object obj, String methodName, boolean newValue) {
try {
invoke(obj, methodName, newValue);
} catch (NoSuchMethodException e) {
// ignore
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static void invokeIfExists(Object obj, String methodName, Class<?> clazz, Object newValue) {
try {
invoke(obj, methodName, clazz, newValue);
} catch (NoSuchMethodException e) {
// ignore
}
}
/**
* Invokes the specified setter method if it exists.
*
* @param obj The object on which to invoke the method.
* @param methodName The name of the method.
*/
public static void invokeIfExistsWithEnum(Object obj, String methodName, String enumClassName, String enumValueName) {
try {
Class<?> enumClass = Class.forName(enumClassName);
Object enumValue = invokeStatic("java.lang.Enum", "valueOf", new Class<?>[] {Class.class, String.class},
new Object[] {enumClass, enumValueName}
);
invoke(obj, methodName, enumClass, enumValue);
} catch (ClassNotFoundException | NoSuchMethodException e) {
// ignore
e.printStackTrace();
}
}
}