/*
 * @(#)Methods.java
 *
 * Copyright (c) 1996-2010 by the original authors of JHotDraw
 * and all its contributors.
 * All rights reserved.
 *
 * The copyright of this software is owned by the authors and  
 * contributors of the JHotDraw project ("the copyright holders").  
 * You may not use, copy or modify this software, except in  
 * accordance with the license agreement you entered into with  
 * the copyright holders. For details see 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: Methods.java 604 2010-01-09 12:00:29Z rawcoder $
 */
@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 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 e) {
            return defaultValue;
        } catch (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).intValue();
        } catch (NoSuchMethodException e) {
            return defaultValue;
        } catch (IllegalAccessException e) {
            return defaultValue;
        } catch (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).longValue();
        } catch (NoSuchMethodException e) {
            return defaultValue;
        } catch (IllegalAccessException e) {
            return defaultValue;
        } catch (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).booleanValue();
        } catch (NoSuchMethodException e) {
            return defaultValue;
        } catch (IllegalAccessException e) {
            return defaultValue;
        } catch (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 e) {
            return defaultValue;
        } catch (IllegalAccessException e) {
            return defaultValue;
        } catch (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).booleanValue();
        } catch (NoSuchMethodException e) {
            return defaultValue;
        } catch (IllegalAccessException e) {
            return defaultValue;
        } catch (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[] { new Boolean(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[] { new Integer(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[] { new Float(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 e) {
            // ignore
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            // ignore
            e.printStackTrace();
        }
    }
}