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一个支持分布式的可以高效开发且可以高效运行的爬虫框架。设计思想上融合了spring与scrapy的优点。
There is a newer version: 2.1.4
package cn.wanghaomiao.seimi.utils;
/*
   Copyright 2015 Wang Haomiao

   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 cn.wanghaomiao.seimi.core.CastToNumber;

import java.lang.reflect.Array;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.math.BigDecimal;
import java.util.HashMap;
import java.util.Map;

/**
 * 实现工具类，检查参数化类型的参数类型。
 */
public class GenericUtils {

    private static final Class[] EMPTY_CLASSES = new Class[0];
    private static final Map numberClass = new HashMap(){{
        put(int.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).intValue();
            }
        });
        put(Integer.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).intValue();
            }
        });
        put(long.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).longValue();
            }
        });
        put(Long.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).longValue();
            }
        });
        put(short.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).shortValue();
            }
        });
        put(Short.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).shortValue();
            }
        });
        put(float.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).floatValue();
            }
        });
        put(Float.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).floatValue();
            }
        });
        put(double.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).doubleValue();
            }
        });
        put(Double.class, new CastToNumber() {
            @Override
            public Object castTo(String ori) {
                return new BigDecimal(ori).doubleValue();
            }
        });
    }};

    /**
     * 从参数, 返回值, 基类的: Generic 类型信息获取传入的实际类信息。
     * 
     * @param genericType - Generic 类型信息
     * @return 实际类信息
     */
    public static Class[] getActualClass(Type genericType) {

        if (genericType instanceof ParameterizedType) {

            Type[] actualTypes = ((ParameterizedType) genericType).getActualTypeArguments();
            Class[] actualClasses = new Class[actualTypes.length];

            int i = 0;
            while (i < actualTypes.length) {
                Type actualType = actualTypes[i];
                if (actualType instanceof Class) {
                    actualClasses[i] = (Class) actualType;
                } else if (actualType instanceof GenericArrayType) {
                    Type componentType = ((GenericArrayType) actualType).getGenericComponentType();
                    actualClasses[i] = Array.newInstance((Class) componentType, 0).getClass();
                }
                i++;
            }

            return actualClasses;
        }

        return EMPTY_CLASSES;
    }

    /**
     * 判断给定类是否是支持的数字类型
     * @param cls
     * @return
     */
    public static boolean isNumber(Class cls){
        return numberClass.containsKey(cls);
    }

    public static Object castToNumber(Class cls,String val){
        return numberClass.get(cls).castTo(val);
    }
}