Java Reflection Annotation getAnnotationValue(Class<? extends Annotation> anno, Field field, String paramName)

Description

get Annotation Value

License

Apache License

Declaration

public static Object getAnnotationValue(Class<? extends Annotation> anno, Field field, String paramName)
            throws Exception

Method Source Code


//package com.java2s;
/*/*from  w  w  w .  j  a v a2s .  co m*/
 * Copyright 2002-2006,2009 The Apache Software Foundation.
 * 
 * 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.annotation.Annotation;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;

import java.util.Iterator;
import java.util.List;

public class Main {
    public static Object getAnnotationValue(Class<? extends Annotation> anno, Field field, String paramName)
            throws Exception {
        Object value = null;
        if (hasAnnotation(anno, field) && (paramName != null && !paramName.isEmpty())) {
            value = callMethodNamed(paramName, field.getAnnotation(anno));
        }
        return value;
    }

    public static Object getAnnotationValue(Class<? extends Annotation> anno, Method meth, String paramName)
            throws Exception {
        Object value = null;
        if (hasAnnotation(anno, meth) && (paramName != null && !paramName.isEmpty())) {
            value = callMethodNamed(paramName, meth.getAnnotation(anno));
        }
        return value;
    }

    public static Object getAnnotationValue(Class<? extends Annotation> anno, Object obj, String paramName)
            throws Exception {
        return getAnnotationValue(anno, obj.getClass(), paramName);
    }

    public static Object getAnnotationValue(Class<? extends Annotation> anno, Class<?> cl, String paramName)
            throws Exception {
        Object value = null;
        if (hasAnnotation(anno, cl) && (paramName != null && !paramName.isEmpty())) {
            value = callMethodNamed(paramName, cl.getAnnotation(anno));
        }
        return value;
    }

    public static Boolean hasAnnotation(Class<? extends Annotation> anno, Field field) {
        return field.isAnnotationPresent(anno);
    }

    public static Boolean hasAnnotation(Class<? extends Annotation> anno, Method meth) {
        return meth.isAnnotationPresent(anno);
    }

    public static Boolean hasAnnotation(Class<? extends Annotation> anno, Object obj) {
        return (getAnnotation(anno, obj) != null);
    }

    public static Boolean hasAnnotation(Class<? extends Annotation> anno, Class<?> cl) {
        return (getAnnotation(anno, cl) != null);
    }

    public static Object callMethodNamed(String name, Object o, Object... p) throws Exception {
        Method toCall = getMethodNamed(name, o);

        if (toCall == null)
            throw new Exception("Il n'y a aucune methode " + name);

        return call(toCall, o, p);
    }

    public static Annotation getAnnotation(Class<? extends Annotation> anno, Class<?> cl) {
        return cl.getAnnotation(anno);
    }

    public static Annotation getAnnotation(Class<? extends Annotation> anno, Object obj) {
        return obj.getClass().getAnnotation(anno);
    }

    public static Annotation getAnnotation(Class<? extends Annotation> anno, Method meth) {
        return meth.getAnnotation(anno);
    }

    public static Annotation getAnnotation(Class<? extends Annotation> anno, Field field) {
        return field.getAnnotation(anno);
    }

    public static Method getMethodNamed(String methodName, Object holder) {
        Method method = null;
        List<Method> all = Arrays.asList(holder.getClass().getDeclaredMethods());
        for (Iterator<Method> iterator = all.iterator(); iterator.hasNext();) {
            Method m = (Method) iterator.next();
            if (methodName.equalsIgnoreCase(m.getName())) {
                method = m;
                break;
            }
        }
        return method;
    }

    public static Object call(Method m, Object o, Object... p) throws Exception {
        Object value = null;
        try {
            m.setAccessible(true);
            value = m.invoke(o, p);
            m.setAccessible(false);
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
            throw new Exception("Les arguments transmis sont mauvais.");
        } catch (IllegalAccessException e) {
            e.printStackTrace();
            throw new Exception("Impossible d'acceder a la methode.");
        } catch (InvocationTargetException e) {
            e.printStackTrace();
            throw new Exception("Erreur dans l'execution.");
        }
        return value;
    }

    public static List<Object> call(final List<Method> lm, final Object o, final Object... p) throws Exception {
        List<Object> values = new ArrayList<Object>();
        for (Iterator<Method> iterator = lm.iterator(); iterator.hasNext();) {
            Method m = (Method) iterator.next();
            values.add(call(m, o, p));
        }
        return values;
    }
}

Java Reflection Annotation getAnnotationValue(Class anno, Field field, String paramName)

Description

License

Declaration

Method Source Code

Related