从提供的类中获取一个Field对象，该对象将对指定方法名称的数据访问进行后端访问

import java.lang.reflect.Field;/** 时 代 J a v a 提 供 **/

import java.lang.reflect.Modifier;

import java.security.AccessController;

import sun.reflect.FieldAccessor;

import sun.reflect.ReflectionFactory;


public class Main{

    /**

     * Get a Field object which backends data access to the given method name,

     * from the supplied class

     * @param m The name of the method

     * @param c The class to get the method from

     * @return a Field with an accessor that backends to the requested Method

     * @throws NoSuchMethodException 

     * @throws IllegalArgumentException 

     * @throws IllegalAccessException 

     */

    public static final Field getMethodField(String m, Class c)

            throws NoSuchMethodException, IllegalArgumentException,

            IllegalAccessException {

        // First, get ANY field at all to use as a base

        Field f = c.getDeclaredFields()[0];

        // Now set up the internal structures to 'look like' the given method

        // but chop up the name so that it is prettier for output

        if (m.startsWith("get") || m.startsWith("set"))

            m = m.substring(3, 4).toLowerCase() + m.substring(4);

        set("name", f, m);

        set("modifiers", f, Modifier.PUBLIC);

        // Finally, override the default FieldAccesors with our own

        FieldAccessor fa = new MethodPseudoAccessor(c, m);/* 来自 时   代    Java - nowjava.com*/

        set("fieldAccessor", f, fa);

        set("overrideFieldAccessor", f, fa);

        return f;

    }

    /**

     * Find the requested Field declared in the target object's class, and set 

     * its value (irrespective of the field's modifiers)

     * @param fi The field name to seek

     * @param target The target object

     * @param v The value to set the field to

     * @throws java.lang.IllegalArgumentException

     * @throws java.lang.IllegalAccessException

     */

    public static final void set(String fi, Object target, Object v)

            throws IllegalArgumentException, IllegalAccessException {

        set(target.getClass(), fi, target, v);

    }

    /**

     * Find the requested Field declared in the given class, and set its value

     * (irrespective of the field's modifiers)

     * @param c The Class to look in

     * @param fi The field name to seek

     * @param target The target object

     * @param v The value to set the field to

     * @throws java.lang.IllegalArgumentException

     * @throws java.lang.IllegalAccessException

     */

    public static final void set(Class c, String fi, Object target, Object v)

            throws IllegalArgumentException, IllegalAccessException {

        for (Field f0 : c.getDeclaredFields())

            if (f0.getName().equals(fi))

                set(f0, target, v);

    }

    /**

     * Set the given field on target to value, irrespective of its modifiers

     * @param f The Field to set

     * @param target The object to set it on

     * @param v The value to set the field to

     * @throws java.lang.IllegalArgumentException

     * @throws java.lang.IllegalAccessException

     */

    public static final void set(Field f, Object target, Object v)