java簡單框架設計

     設計框架包能夠做爲一個工具給你們用，須要有徹底不一樣設計思路給出來，不一樣於咱們去作一個web服務、網站、

或者一個業務微服務，須要從原來使用視角轉換成一個構建者視角。

 

     框架或者工具，更可能是框架來管理或者說調用咱們，咱們來遵循框架原則來實現，框架和業務實現上的核心差別。

     java框架，能夠依賴註解以及抽象類來實現邏輯，實現基於註解配置，經過註解簡化配置方式。子類實現抽象類，

子類中的註解對象能夠用過反射方式在框架中被調用，從而實現一個簡單的框架。  

 

註解類：

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

//註解配置信息字段.
@Target({ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface DeskConf {

    String getComponent() default "";

    String value();
}
抽象類：

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

//註解配置信息字段.
@Target({ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface DeskConf {

    String getComponent() default "";

    String value();
}
解析工具：

import org.apache.log4j.Logger;

import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;

/**
 * 讀取註解信息
 */
public class ConfigAnnotationParse {
    protected Logger logger = Logger.getLogger(ConfigAnnotationParse.class);
    private ConfRegister configRegister;

    public ConfigAnnotationParse(ConfRegister configCenter) {
        this.configRegister = configCenter;
    }



    public DeskConf parseNodeAnnotation() throws Exception {
        if (configRegister == null)
            throw new ExceptionInInitializerError("ConfigRegister 統一配置註冊中心必須被繼承實現");
        Class clazz = configRegister.getClass();
        Map<String,String> nodeMap = new HashMap<String,String>();
        DeskConf deskConf = null;
        Field[] fields = clazz.getDeclaredFields();
        for(Field field : fields) {
            if (field.isAnnotationPresent(DeskConf.class)) {
                deskConf = field.getAnnotation(DeskConf.class);
            }
        }
        return deskConf;
    }

}

使用樣例：

import org.apache.log4j.Logger;

import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;

/**
 * 讀取註解信息
 */
public class ConfigAnnotationParse {
    protected Logger logger = Logger.getLogger(ConfigAnnotationParse.class);
    private ConfRegister configRegister;

    public ConfigAnnotationParse(ConfRegister configCenter) {
        this.configRegister = configCenter;
    }



    public DeskConf parseNodeAnnotation() throws Exception {
        if (configRegister == null)
            throw new ExceptionInInitializerError("ConfigRegister 統一配置註冊中心必須被繼承實現");
        Class clazz = configRegister.getClass();
        Map<String,String> nodeMap = new HashMap<String,String>();
        DeskConf deskConf = null;
        Field[] fields = clazz.getDeclaredFields();
        for(Field field : fields) {
            if (field.isAnnotationPresent(DeskConf.class)) {
                deskConf = field.getAnnotation(DeskConf.class);
            }
        }
        return deskConf;
    }

}

接口：

public interface ConfService {

    /**
     * 獲取配置信息
     * @param name 項目名稱.
     * @param key key名稱.
     * @return
     */
    String getConf(String name,String key);

    /**
     * 得到所屬模塊.
     * @return
     */
    String  getComponent();
}

實現類：

public class ConfServiceImpl implements ConfService {
    private ConfRegister myConfRegister;
    private DeskConf deskConf;

    /**
     *
     * @param confRegister
     * @throws Exception
     */
    public ConfServiceImpl(ConfRegister confRegister) throws Exception {
        this.myConfRegister = confRegister;
        ConfigAnnotationParse configAnnotationParse = new ConfigAnnotationParse(myConfRegister);
        deskConf = configAnnotationParse.parseNodeAnnotation();
    }

    /**
     * 獲取配置項信息
     * @param name 項目名稱.
     * @param key key名稱.
     * @return
     */
    public String getConf(String name, String key) {
        if(deskConf==null)
            return null;

        String component = deskConf.getComponent();
        Conf conf = new Conf();
        conf.setComponent(component);
        conf.setName(name);
        conf.setKey(key);

        String value = DBConf.getValue(conf);

        return value;
    }


    /**
     * 得到所屬模塊.
     * @return
     */
    public String getComponent() {
        if(deskConf==null)
            return null;

        String component = deskConf.value();

        return component;
    }


}

2、jar包配置使用方式

一、maven依賴

<dependency>
   <groupId>com.jd.app.server</groupId>
   <artifactId>desk-conf</artifactId>
   <version>1.0.0-SNAPSHOT</version>
</dependency>

二、配置項注入樣例

/**
 * 
 */
public class TimeConstants extends ConfRegister{

    @DeskConf("online")
    private static String comp = "";

}

三、spring-config.xml 主配置文件中配置

<bean id="timeConstants" class="com.common.constant.TimeConstants"></bean>
<bean id="confService" class="com.jd.app.server.service.impl.ConfServiceImpl">
    <constructor-arg index="0" ref="timeConstants"/>
</bean>

四、使用說明

@Autowired
ConfService confService;

讀取監控信息

String value = confService.getConf("findgood","down");

讀取模塊名稱

String com = confService.getComponent();