Java Reflection Method Getter Get getGetter(Class _class, String fieldName)

Description

get Getter

License

Apache License

Declaration

public static Method getGetter(Class _class, String fieldName) throws NoSuchMethodException 

Method Source Code

//package com.java2s;
/*/*from  ww w. j a  v a  2 s  .  co m*/
 * Copyright 2010 Kodapan
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.*;

public class Main {
    public static Method getGetter(Field field) throws NoSuchMethodException {
        StringBuilder getterName = new StringBuilder(field.getName().length() + 3);
        if (field.getType() == java.lang.Boolean.class || field.getType() == boolean.class) {
            getterName.append("is");
        } else {
            getterName.append("get");
        }
        getterName.append(field.getName().substring(0, 1).toUpperCase());
        getterName.append(field.getName().substring(1));
        return field.getDeclaringClass().getMethod(getterName.toString());
    }

    public static Method getGetter(Class _class, String fieldName) throws NoSuchMethodException {
        return getGetter(gatherAllBeanFields(_class).get(fieldName));
    }

    public static Method getGetter(Object instance, String fieldName) throws NoSuchMethodException {
        return getGetter(instance.getClass(), fieldName);
    }

    public static Map<String, Field> gatherAllBeanFields(Class implementation) {
        return gatherAllBeanFields(gatherAllClasses(implementation));
    }

    public static Map<String, Field> gatherAllBeanFields(Set<Class> allClasses) {
        Map<String, Field> allFields = new HashMap<String, Field>();
        for (Class _class : allClasses) {
            for (Field field : Arrays.asList(_class.getDeclaredFields())) {
                if (!Modifier.isFinal(field.getModifiers()) && !Modifier.isTransient(field.getModifiers())
                        && !Modifier.isStatic(field.getModifiers())) {
                    allFields.put(field.getName(), field);
                }
            }
        }
        return allFields;
    }

    public static Set<Class> gatherAllClasses(Class implementation) {
        Set<Class> classes = new HashSet<Class>();
        gatherAllClasses(implementation, classes);
        return classes;
    }

    public static void gatherAllClasses(Class implementation, Set<Class> classes) {
        classes.add(implementation);
        if (implementation.getSuperclass() != null && classes.add(implementation.getSuperclass())) {
            gatherAllClasses(implementation.getSuperclass(), classes);
        }
        for (Class _class : implementation.getInterfaces()) {
            if (classes.add(_class)) {
                gatherAllClasses(_class, classes);
            }
        }
    }
}

Related

1. getGetter(A instance, String strAttributeName, Class clazz)
2. getGetter(Class c, Field field)
3. getGetter(Class clazz, String name)
4. getGetter(Class clazz, Field field)
5. getGetter(Class clazz, Field field)