Spring编写实例

1 BeandefinitionRegister

package com.example03.support;

import com.example03.BeanDefinition;
import org.springframework.beans.factory.BeanDefinitionStoreException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;



public interface BeanDefinitionRegistry {
    
    
    void registerBeanDefinition(String var1, BeanDefinition var2) throws BeanDefinitionStoreException;

    void removeBeanDefinition(String var1) throws NoSuchBeanDefinitionException;

    BeanDefinition getBeanDefinition(String var1) throws NoSuchBeanDefinitionException;

    boolean containsBeanDefinition(String var1);

    String[] getBeanDefinitionNames();

    int getBeanDefinitionCount();


}

2 SimpleBeanDefinitionRegister

package com.example03;

import com.example03.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.BeanDefinitionStoreException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;


import java.util.HashMap;
import java.util.Map;

public class SimpleBeanDefinitionRegistry implements BeanDefinitionRegistry {
    
    
    Map<String, BeanDefinition> beanDefinitionMap=new HashMap<>();


    @Override
    public void registerBeanDefinition(String var1, BeanDefinition var2) throws BeanDefinitionStoreException {
    
    
        this.beanDefinitionMap.put(var1,var2);
    }

    @Override
    public void removeBeanDefinition(String var1) throws NoSuchBeanDefinitionException {
    
    
        this.beanDefinitionMap.remove(var1);
    }

    @Override
    public BeanDefinition getBeanDefinition(String var1) throws NoSuchBeanDefinitionException {
    
    
        return this.beanDefinitionMap.get(var1);
    }

    @Override
    public boolean containsBeanDefinition(String var1) {
    
    
        return this.beanDefinitionMap.containsKey(var1);
    }

    @Override
    public String[] getBeanDefinitionNames() {
    
    
        return beanDefinitionMap.keySet().toArray(new String[0]);
    }

    @Override
    public int getBeanDefinitionCount() {
    
    
        return beanDefinitionMap.size();
    }

}

3 MutablePropertyValues

package com.example03;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Spliterator;
import java.util.function.Consumer;

public class MutablePropertyValues implements Iterable<PropertyValue>{
    
    
    private final List<PropertyValue> propertyValueList;

    public MutablePropertyValues() {
    
    
        this.propertyValueList=new ArrayList<PropertyValue>();
    }

    public MutablePropertyValues(List<PropertyValue> propertyValueList) {
    
    
        if(propertyValueList==null){
    
    
            this.propertyValueList=new ArrayList<PropertyValue>();
        }else {
    
    
            this.propertyValueList = propertyValueList;
        }
    }

    @Override
    public Iterator iterator() {
    
    
        return propertyValueList.iterator();
    }

    public PropertyValue[] getPropertyValues(){
    
    
        return propertyValueList.toArray(new PropertyValue[0]);
    }
    public PropertyValue getPropertyValue(String propertyName){
    
    
        for (PropertyValue propertyValue : propertyValueList) {
    
    
            if(propertyValue.getName().equals(propertyName)){
    
    
                return propertyValue;
            }

        }
        return null;
    }
    public boolean isEmpty(){
    
    
        return propertyValueList.isEmpty();
    }
    public MutablePropertyValues addPropertyValues(PropertyValue propertyValue){
    
    
        for (int i = 0; i < propertyValueList.size(); i++) {
    
    
            PropertyValue propertyValue1=propertyValueList.get(i);
            if(propertyValue1.getName().equals(propertyValue.getName())){
    
    
                propertyValueList.set(i,propertyValue);
                return this;
            }
            
        }
        propertyValueList.add(propertyValue);
        return this;
    }
    public boolean contains(String propertyName){
    
    
        return propertyValueList.contains(propertyName);

    }
}

4 PropertyValue

package com.example03;

public class PropertyValue {
    
    
    private String name;
    private String ref;
    private String value;

    public PropertyValue() {
    
    
    }

    public PropertyValue(String name, String ref, String value) {
    
    
        this.name = name;
        this.ref = ref;
        this.value = value;
    }

    public String getName() {
    
    
        return name;
    }

    public void setName(String name) {
    
    
        this.name = name;
    }

    public String getRef() {
    
    
        return ref;
    }

    public void setRef(String ref) {
    
    
        this.ref = ref;
    }

    public String getValue() {
    
    
        return value;
    }

    public void setValue(String value) {
    
    
        this.value = value;
    }
}

5 BeanDefinition

package com.example03;

public class BeanDefinition {
    
    
    private String id;
    private String className;
    private MutablePropertyValues mutablePropertyValues;

    public BeanDefinition() {
    
    
        this.mutablePropertyValues=new MutablePropertyValues();
    }

    public String getId() {
    
    
        return id;
    }

    public void setId(String id) {
    
    
        this.id = id;
    }

    public String getClassName() {
    
    
        return className;
    }

    public void setClassName(String className) {
    
    
        this.className = className;
    }

    public MutablePropertyValues getMutablePropertyValues() {
    
    
        return mutablePropertyValues;
    }

    public void setMutablePropertyValues(MutablePropertyValues mutablePropertyValues) {
    
    
        this.mutablePropertyValues = mutablePropertyValues;
    }

    @Override
    public String toString() {
    
    
        return "BeanDefinition{" +
                "id='" + id + '\'' +
                ", className='" + className + '\'' +
                ", mutablePropertyValues=" + mutablePropertyValues +
                '}';
    }
}

6 BeanDefinitionReader

package com.example03.support;



public interface BeanDefinitionReader {
    
    
    BeanDefinitionRegistry getRegistry();

    void loadBeanDefinition(String configLocation) throws Exception;


}

7 XmlBeanDefinitionReader

package com.example03;

import com.example03.support.BeanDefinitionReader;
import com.example03.support.BeanDefinitionRegistry;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

import java.io.InputStream;
import java.util.List;

public class XmlBeanDefinitionReader implements BeanDefinitionReader {
    
    
    private BeanDefinitionRegistry beanDefinitionRegistry;
    public XmlBeanDefinitionReader() {
    
    
        this.beanDefinitionRegistry=new SimpleBeanDefinitionRegistry();
    }

    @Override
    public BeanDefinitionRegistry getRegistry() {
    
    
        return beanDefinitionRegistry;
    }

    @Override
    public void loadBeanDefinition(String configLocation) throws Exception {
    
    
         SAXReader  reader=new SAXReader();
        InputStream resourceAsStream = XmlBeanDefinitionReader.class.getClassLoader().getResourceAsStream(configLocation);
        Document read = reader.read(resourceAsStream);
        Element rootElement = read.getRootElement();
        parseElelment(rootElement);

    }
    public void parseElelment(Element rootElements){
    
    
        List<Element> elements = rootElements.elements();
        for (Element element : elements) {
    
    
            String id=element.attributeValue("id");
            String className=element.attributeValue("class");
            BeanDefinition beanDefinition = new BeanDefinition();
            beanDefinition.setId(id);
            beanDefinition.setClassName(className);
            MutablePropertyValues propertyValues = new MutablePropertyValues();
            List<Element> elements1 = element.elements();
            for (Element element1 : elements1) {
    
    
                String name = element1.attributeValue("name");
                String ref = element1.attributeValue("ref");
                String value = element1.attributeValue("value");
                PropertyValue propertyValue=new PropertyValue(name,ref,value);
                propertyValues.addPropertyValues(propertyValue);

            }
            beanDefinition.setMutablePropertyValues(propertyValues);
            System.out.println(beanDefinition);
            System.out.println(beanDefinition);
            beanDefinitionRegistry.registerBeanDefinition(id,beanDefinition);



        }


    }

    public static void main(String[] args) throws Exception {
    
    
        XmlBeanDefinitionReader xmlBeanDefinitionReader = new XmlBeanDefinitionReader();
        xmlBeanDefinitionReader.loadBeanDefinition("config.xml");

    }
}

8 ApplicationContext

package com.example03.support;

import com.example03.support.BeanFactory;

public interface ApplicationContext extends BeanFactory {
    
    
    void refresh() throws Exception;
}

9 AbstractApplicationContext

package com.example03;

import com.example03.support.ApplicationContext;
import com.example03.support.BeanDefinitionReader;
import com.example03.support.BeanDefinitionRegistry;

import java.util.HashMap;
import java.util.Map;

public abstract class AbstractApplicationContext implements ApplicationContext {
    
    
    protected BeanDefinitionReader beanDefinitionReader;
    protected Map<String,Object> singletonObject=new HashMap<>();
    protected String configLocation;

    @Override
    public void refresh() throws Exception {
    
    
        beanDefinitionReader.loadBeanDefinition(configLocation);
        finishBeanInitialization();

    }

    protected  void finishBeanInitialization() throws Exception {
    
    
        BeanDefinitionRegistry registry = beanDefinitionReader.getRegistry();
        String[] beanDefinitionNames = registry.getBeanDefinitionNames();
        for (String beanDefinitionName : beanDefinitionNames) {
    
    
            getBean(beanDefinitionName);

        }

    };
}

10 ClassPathApplicationContext

package com.example03;

import com.example03.support.BeanDefinitionRegistry;
import com.example03.util.StringUtils;

import java.lang.reflect.Method;

public class ClassPathXmlApplicationContext extends AbstractApplicationContext{
    
    
    public ClassPathXmlApplicationContext(String configLoaction) throws Exception {
    
    
        this.configLocation=configLoaction;
        this.beanDefinitionReader=new XmlBeanDefinitionReader();
        this.refresh();
    }
    //根据bean的对象名称获取bean对象
    @Override
    public Object getBean(String beanName) throws Exception {
    
    
        //判断对象容器中是否包含指定名称的对象，有就返回，没有则创建
        Object obj = singletonObject.get(beanName);
        if(obj != null){
    
    
            return obj;
        }
        //自行创建，获取benaDefinition
        BeanDefinitionRegistry registry = beanDefinitionReader.getRegistry();
        BeanDefinition beanDefinition = registry.getBeanDefinition(beanName);

        //通过反射创建对象
        String className = beanDefinition.getClassName();
        Class clazz = Class.forName(className);
        Object beanobj = clazz.newInstance(); //实例化
        //需要进行依赖注入
        MutablePropertyValues mutablePropertyValues = beanDefinition.getMutablePropertyValues();
        for (PropertyValue mutablePropertyValue : mutablePropertyValues) {
    
    
            //获取property属性
            String pname = mutablePropertyValue.getName();
            String ref = mutablePropertyValue.getRef();
            String value = mutablePropertyValue.getValue();
            if(ref != null && !"".equals(ref)){
    
    
                //获取依赖的对象
                Object bean = getBean(ref);
                //setCourceDao set+courceDao
                String setterMethod = StringUtils.getSetterMethod(pname);
                //获取所有的方法对象
                Method[] methods = clazz.getMethods();
                for (Method method : methods) {
    
    
                    if(setterMethod.equals(method)){
    
    
                        //执行该方法
                        method.invoke(beanobj,bean);
                    }

                }
            }
            if (value != null && !"".equals(value)){
    
    
                String setterMethod = StringUtils.getSetterMethod(value);
                //获取method
                Method method = clazz.getMethod(setterMethod, String.class);
                method.invoke(beanobj, value);

            }



        }
        //返回beanObj之前 需要将对象存储到map容器中
        this.singletonObject.put(beanName,beanobj);

        return beanobj;
    }

    @Override
    public <T> T getBean(String name, Class<? extends T> clazz) throws Exception {
    
    
        Object bean = getBean(name);
        if(bean ==null ){
    
    
            return null;
        }

        return clazz.cast(bean);
    }
}

11 StringUtils

package com.example03.util;

public class StringUtils {
    
    
    public StringUtils() {
    
    
    }
    public static  String getSetterMethod(String fileName){
    
    
        String methodName="set"+fileName.substring(0,1).toUpperCase()+fileName.substring(1);
        return methodName;
    }
}