dubbo-spring自定义标签

一、首先建立一个自主定义的标签xsd文件，可以放入自己想定义的任意名称的标签

<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns="http://www.mahongb.com/schema/soa"
	xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.mahongb.com/schema/soa"
 elementFormDefault="qualified" attributeFormDefault="unqualified">
	<xsd:element name="myTest">
		<xsd:complexType>
			<xsd:attribute name="test" type="xsd:string"></xsd:attribute>
		</xsd:complexType>
	</xsd:element>
	
	<xsd:element name="service">
		<xsd:complexType>
			<xsd:attribute name="interface" type="xsd:string"></xsd:attribute>
			<xsd:attribute name="ref" type="xsd:string"></xsd:attribute>
		</xsd:complexType>
	</xsd:element>
</xsd:schema>

    此处定义标签myTest，里面有子标签test，类型为String类型；定义标签service，里面有子标签interface与ref，类型都是String

二、定义标签实体类，接收标签元素与其子元素

package cn.spring.configBean;

public class Mytest {
	private String test;

	public String getTest() {
		return test;
	}

	public void setTest(String test) {
		this.test = test;
	}
}

package cn.spring.configBean;

public class Service {
	private String inter;
	private String ref;
	public String getInter() {
		return inter;
	}
	public void setInter(String inter) {
		this.inter = inter;
	}
	public String getRef() {
		return ref;
	}
	public void setRef(String ref) {
		this.ref = ref;
	}
}

     以自定义的标签为名生成标签类，其中的子标签为类中的元素，类型为标签中的类型

三、建立处理标签的类，主要用来进行标签的解释，即标签与实体类对应起来

package cn.spring.parse;

import org.springframework.beans.factory.xml.NamespaceHandlerSupport;

import cn.spring.configBean.Mytest;
import cn.spring.configBean.Service;
public class SOANamespaceHandler extends NamespaceHandlerSupport {

	public void init() {
		registerBeanDefinitionParser("myTest", 
				new MytestBeanDefinitionParse(Mytest.class));
		registerBeanDefinitionParser("service", 
				new ServiceBeanDefinitionParse(Service.class));
	}
}

    此处的解释类需要继承 NamespaceHandlerSupport 这个类，实现init方法完成标签的解释

三、建立解析自定义标签的类

package cn.spring.parse;

import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.beans.factory.xml.BeanDefinitionParser;
import org.springframework.beans.factory.xml.ParserContext;
import org.w3c.dom.Element;

public class MytestBeanDefinitionParse implements BeanDefinitionParser {
	private Class<?> beanclass;
	
	public MytestBeanDefinitionParse(Class<?> beanclass){
		this.beanclass = beanclass;
	}
	
	public BeanDefinition parse(Element arg0, ParserContext arg1) {
		RootBeanDefinition beanDefinition = new RootBeanDefinition();
		beanDefinition.setBeanClass(beanclass);
		beanDefinition.setLazyInit(false);
		
		String test = arg0.getAttribute("test");
		if(test == null || "".equals(test)){
			throw new RuntimeException("test不能为null");
		}
		
		beanDefinition.getPropertyValues().addPropertyValue("test", test);
		
		return beanDefinition;
	}
} 

进行标签 mytest 的解析

package cn.spring.parse;

import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.beans.factory.xml.BeanDefinitionParser;
import org.springframework.beans.factory.xml.ParserContext;
import org.w3c.dom.Element;

public class ServiceBeanDefinitionParse implements BeanDefinitionParser {
	private Class<?> beanclass;
	
	public ServiceBeanDefinitionParse(Class<?> beanclass){
		this.beanclass = beanclass;
	}
	
	public BeanDefinition parse(Element arg0, ParserContext arg1) {
		RootBeanDefinition beanDefinition = new RootBeanDefinition();
		beanDefinition.setBeanClass(beanclass);
		beanDefinition.setLazyInit(false);
		
		String inter = arg0.getAttribute("interface");
		String ref = arg0.getAttribute("ref");
		
		if(inter == null || "".equals(inter)){
			throw new RuntimeException("interface不能为空");
		}
		if(ref == null || "".equals(ref)){
			throw new RuntimeException("ref不能为空");
		}
		beanDefinition.getPropertyValues().addPropertyValue("inter", inter);
		beanDefinition.getPropertyValues().addPropertyValue("ref", ref);
		return beanDefinition;
	}
}

进行标签 service 的解析

四、spring读取我们自定义的schema和handlers默认是根据spring.handlers和spring.schemas来读取的，这两个文件默认要放在META-INF下

http\://www.dongnaoedu.com/schema/soa.xsd=META-INF/soa.xsd

     spring.schemas 文件使用指定路径下的文件 META-INF/soa.xsd 来生成自定义标签

http\://www.dongnaoedu.com/schema/soa=cn.spring.parse.SOANamespaceHandler

    spring.handlers 文件使用指定包名下的类 SOANamespaceHandler 来进行标签类的解释，与实体类对应起来

五、建立xml文件进行检验

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" 
	   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	   xmlns:mhb="http://www.mahongb.com/schema/soa"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
	   http://www.dongnaoedu.com/schema/soa 
	   http://www.dongnaoedu.com/schema/soa.xsd"
       default-lazy-init="true">
	<bean id="userSreviceImp" class="cn.spring.test.UserServiceImp"></bean>
	<mhb:service interface="cn.spring.test.UserService" ref="userSreviceImp"></mhb:service>
 	<mhb:myTest test="mhb"></mhb:myTest>
</beans>