spring bean单例注入与用单例模式通过class.getinstance(）区别？

1、action的某个方法中，用以下代码获得redis单例实例

RedisDelegate  redisDelegate = RedisDelegate.getInstance();

redisDelegate.set(0, q1, result.toString());

2、Redisdelegate的单例模式如下

	/**
	 * 私有构造器
	 */
	private RedisDelegate() {
		System.out.println("创建实例对象！");
		JedisPoolConfig config = new JedisPoolConfig();
		config.setMaxTotal(30);  //2.5.2之前的版本是setMaxActive
		config.setMaxIdle(10);
		config.setMaxWaitMillis(3*1000);  //2.5.2之前的版本是setMaxWait
		this.jedisPool = new JedisPool(config, REDIS_HOST,REDIS_PORT, 5000,"123");
	}

	/**
	 * @function: 创建redisDelegate单例
	 * 懒汉式
	 * @createTime 2014年11月4日 下午7:03:27
	 */
	public  synchronized  static  RedisDelegate getInstance() {
		if(instance == null) {
			System.out.println("懒汉式--单例模式，创建RedisDelegate实例！");
		    instance = new RedisDelegate();
		}
		return instance;
	}
	

3、运行web应用程序，发布在tomcat下，action中方法被执行，但是

RedisDelegate  redisDelegate = RedisDelegate.getInstance();

报错如下：

十一月 05, 2014 4:24:46 下午 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet [controller] in context with path [/adjustSolr] threw exception [Handler processing failed; nested exception is java.lang.NoClassDefFoundError: redis/clients/jedis/JedisPoolConfig] with root cause
java.lang.ClassNotFoundException: redis.clients.jedis.JedisPoolConfig
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1720)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571)
	at com.solr.adjust.controller.TestAction.testjedis(TestAction.java:13)
	at com.solr.adjust.controller.ConfigAction.configSearch(ConfigAction.java:61)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219)
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:100)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:604)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:565)
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)

4、如果就走main方法或者实例化其他类，通过其他类的方法实例化redisDelegate则不报错误

public class TestAction {

	public static void main(String []args){
		new TestAction().testjedis();
	}

  public void testjedis(){
	  RedisDelegate  redisDelegate = RedisDelegate.getInstance();
	  redisDelegate.set(0, "测试key111", "测试value1111");
	  System.out.println("测试开始！！！");

  }

在回到1步骤，添加以下代码执行是没有问题

    TestAction  test = new TestAction();
	    test.testjedis();

求问原因！！！！！！！！！！！！！！！！

是因为spring框架中，只能通过注入或者直接调用构造函数创建实例，而不能直接采用懒汉式单例模式创建实例？？？？？？？？？？？？？

罪魁祸首JedisPoolConfig，当用spring的时候，必须结合spring来用，配置到配置文件中。

没有spring时候可以独立实例化JedisPoolConfig