java实现Spring在XML配置java类的方法

1. 创建自己的bean文件：beans.xml

<?xml version="1.0" encoding="utf-8"?>
<busi-beans>
	<beans>
		<bean id="syshelloimpl" type="com.cxm.test.syshello">
			<desc>test</desc>
			<impl-class>com.cxm.test.syshelloimpl</impl-class>
		</bean>		
	</beans>		
</busi-beans>

2. 提供解析xml类：xmlutils

/**
 * 
 */
package com.cxm.xmlutil;

import java.io.inputstream;
import java.util.iterator;
import java.util.map;

import org.jdom.attribute;
import org.jdom.document;
import org.jdom.element;
import org.jdom.input.saxbuilder;
import org.jdom.xpath.xpath;

import com.cxm.beaninfo.beaninfo;



/**
 * @author admin
 * 
 */
public class xmlutils
{
	
	public static void parsexmldef(inputstream in, map<string,beaninfo> beandefmap,
			stringbuffer sb) throws exception
	{
		saxbuilder reader = new saxbuilder(false);
		document doc = null;
		try
		{
			doc = reader.build(in);
			iterator beanit = xpath.selectnodes(doc, "/busi-beans/beans/bean")
					.iterator();
			element e;
			beaninfo beandef;
			while (beanit.hasnext())
			{
				beandef = new beaninfo();
				e = (element) beanit.next();
				attribute attrid = e.getattribute("id");
				attribute attrtype = e.getattribute("type");
				attribute singletype = e.getattribute("single");
				boolean issingle = true;
				if(null != singletype&&"1".equals(singletype.getvalue())){
					issingle= false;
				}
				beandef.setsingle(issingle);
				beandef.setbeanid(attrid.getvalue());
				beandef.settype(attrtype.getvalue());
				beandef.setbeandesc(gettext(e, "desc"));
				beandef.setimplclassname(gettext(e, "impl-class"));
				//处理初始化参数
				beandefmap.put(attrid.getvalue(), beandef);
			}
		}
		catch (exception e)
		{
			e.printstacktrace();
		}
	}
	
	/**
	 * 根据指定的element, xpath获取xml文档内容
	 * 
	 * @param p_element
	 * @param p_xpath
	 * @return
	 * @throws exception
	 */
	public static string gettext(element p_element, string p_xpath)
			throws exception {
		string text = null;
		element e=(element)xpath.selectsinglenode(p_element,p_xpath);
		if (e != null) {
			text = e.gettext();
		} else {
		}
		return text;
	}
}

3.定义bean io

/**
 * 
 */
package com.cxm.beaninfo;

/**
 * @author admin
 *
 */
public class beaninfo
{
	private string beanid;
	
	private string type;
	
	private string beandesc;
	
	public string getbeandesc()
	{
		return beandesc;
	}

	public void setbeandesc(string beandesc)
	{
		this.beandesc = beandesc;
	}

	public string gettype()
	{
		return type;
	}

	public void settype(string type)
	{
		this.type = type;
	}

	private string implclassname;
	
	public string getbeanid()
	{
		return beanid;
	}

	public void setbeanid(string beanid)
	{
		this.beanid = beanid;
	}
	
	public string getimplclassname()
	{
		return implclassname;
	}

	public void setimplclassname(string implclassname)
	{
		this.implclassname = implclassname;
	}

	public boolean issingle()
	{
		return issingle;
	}

	public void setsingle(boolean issingle)
	{
		this.issingle = issingle;
	}

	private boolean issingle = true;
	
}

4.bean的创建类：beanutil

/**
 * 
 */
package com.cxm.bean;



/**
 * @author admin
 *
 */
public class beanutil
{
	private static xmlbeanfactory factory = new xmlbeanfactory();
	/**
	 * 获取定义好的bean对象
	 * @param p_beanid
	 * @return
	 * @throws exception 
	 */
	public static object createbean(string p_beanid)
			throws exception {
		return factory.createbean(p_beanid);
	}
}

 

/**
 * 
 */
package com.cxm.bean;

import java.io.filenotfoundexception;
import java.io.inputstream;
import java.lang.reflect.constructor;
import java.util.hashmap;
import java.util.map;

import com.cxm.beaninfo.beaninfo;
import com.cxm.exception.nosuchbeandefinitionexception;
import com.cxm.xmlutil.xmlutils;

/**
 * @author admin
 *
 */
public class xmlbeanfactory
{
	private static string bean_xml = "/beans.xml";
	
	private static map<string,beaninfo> beandefmap = new hashmap<string,beaninfo>();
	
	private static map<string,object> instancemap = new hashmap<string,object>();
	
	static {
		inputstream in = xmlbeanfactory.class.getresourceasstream(bean_xml);
		if(in ==null){
			try{
				throw new filenotfoundexception();
			}catch (filenotfoundexception e){
				e.printstacktrace();
			}
		}
		stringbuffer sb = new stringbuffer();
		try
		{
			xmlutils.parsexmldef(in, beandefmap, sb);
		}
		catch (exception e)
		{
			throw new runtimeexception();
		}
	}
	
	public object createbean(string beanid) throws exception{
		if(beanid==null || beanid.trim()==""){
			throw new exception("beanid can not null or '' ");
		}
		beaninfo beaninfo = beandefmap.get(beanid);
		if(null ==beaninfo ){
			throw new nosuchbeandefinitionexception(" beanid is not define in xml");
		}
		object instance;
		if(beaninfo.issingle()){
			instance =instancemap.get(beanid);
			if(null != instance){
				return instance;
			}
		}
		string implclass = beaninfo.getimplclassname();
		constructor<?> constructor = class.forname(implclass.trim()).getconstructor();
		instance = constructor.newinstance();
		if(beaninfo.issingle()){
			instancemap.put(beanid, instance);
		}
		return instance;
	}
}

5. 测试：

/**
 * 
 */
package com.cxm.test;

/**
 * @author admin
 *
 */
public interface syshello
{
	void syshello();
}

 

/**
 * 
 */
package com.cxm.test;

/**
 * @author admin
 *
 */
public class syshelloimpl implements syshello
{

	@override
	public void syshello()
	{
		system.out.println("hello world!");
		
	}
	
}

 

/**
 * 
 */
package com.cxm.test;

import com.cxm.bean.beanutil;

/**
 * @author admin
 *
 */
public class test
{
	
	/**
	 * @param args
	 * @throws exception 
	 */
	public static void main(string[] args) throws exception
	{
		syshello s = (syshello)beanutil.createbean("syshelloimpl");
		s.syshello();
	}
	
}

以上这篇java实现spring在xml配置java类的方法就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持。