Java Method Call invokeExactField(Object object, String fieldName)

Description

Retrieve a field whose value is returned as an object.

License

Apache License

Parameter

Parameter	Description
object	invoke method on this object
fieldName	the field to be probed

Exception

Parameter	Description
NoSuchFieldException	if there is no such accessible field
InvocationTargetException	wraps an exception thrown by the method invoked
IllegalAccessException	if the requested method is not accessible via reflection

Declaration

public static Object invokeExactField(Object object, String fieldName)
        throws NoSuchFieldException, IllegalAccessException, InvocationTargetException 

Method Source Code

//package com.java2s;
/*//  w w w.  j a  va  2 s .  c o  m
 * ====================================================================
 *
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Commons", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;

public class Main {
    /**
     * <p>
     * Retrieve a field whose value is returned as an object.
     * </p>
     * 
     * <p>
     * This uses reflection to invoke the field obtained from a call to
     * {@link #getDeclaredField}.
     * </p>
     * 
     * @param object
     *            invoke method on this object
     * @param fieldName
     *            the field to be probed
     * 
     * @throws NoSuchFieldException
     *             if there is no such accessible field
     * @throws InvocationTargetException
     *             wraps an exception thrown by the method invoked
     * @throws IllegalAccessException
     *             if the requested method is not accessible via reflection
     */
    public static Object invokeExactField(Object object, String fieldName)
            throws NoSuchFieldException, IllegalAccessException, InvocationTargetException {
        Field field = object.getClass().getDeclaredField(fieldName);
        if (field == null)
            throw new NoSuchFieldException(
                    "No such accessible field: " + fieldName + " on object: " + object.getClass().getName());
        return field.get(object);
    }
}

Related

1. invokeDeclaredMethod(Object object, String methodName, Object... parameters)
2. invokeDeclaredMethod(String methodName, Object target, Class[] parameterTypes, Object[] parameters)
3. invokeDeclaredMethodWithAnnotation(Class annotationClass, Object target)
4. invokeDefaultMethod(final Method method, final Object[] args, final Object proxy)
5. invokedMethod(java.lang.Object closure, java.lang.Class targetClass, java.lang.String targetMethod)
6. invokeExactMethod(Object object, String methodName, Object[] args, Class[] parameterTypes)
7. invokeFunction(Object iFunction, String funcName, String param)
8. invokeFunctions(Object iFunction, String funcName)
9. invokeGenericMethodOneArg(final Object obj, final String methodName, final Object arg)