Positioned Update not supported异常解决方法

今天在SSH项目中遇到运用JSON插件，产生如下异常：

2008-11-15 12:58:21 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet default threw exception
java.sql.SQLException: Positioned Update not supported.
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926)
	at com.mysql.jdbc.ResultSetImpl.getCursorName(ResultSetImpl.java:2050)
	at com.mchange.v2.c3p0.impl.NewProxyResultSet.getCursorName(NewProxyResultSet.java:545)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:224)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.add(JSONWriter.java:321)
	at com.googlecode.jsonplugin.JSONWriter.bean(JSONWriter.java:225)
	at com.googlecode.jsonplugin.JSONWriter.process(JSONWriter.java:157)
	at com.googlecode.jsonplugin.JSONWriter.value(JSONWriter.java:123)
	at com.googlecode.jsonplugin.JSONWriter.write(JSONWriter.java:91)
	at com.googlecode.jsonplugin.JSONUtil.serialize(JSONUtil.java:90)
	at com.googlecode.jsonplugin.JSONResult.execute(JSONResult.java:173)
	at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:348)
	at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:253)
	at zz.WebNews.util.AuthorizationInterceptor.intercept(AuthorizationInterceptor.java:62)
	at com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224)
	at com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223)
	at com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455)
	at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221)
	at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:50)
	at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:504)
	at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:419)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at zz.WebNews.util.AuthFilter.doFilter(AuthFilter.java:62)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
	at java.lang.Thread.run(Unknown Source)

该异常有两种解决方法：
第一：在struts.xml文件的配置中排除不要被JSON序列化的属性，例如：

<action name="functions" class="getFunctionsAction" method="functions_getList">
    		<result type="json">
    		 <param name="excludeProperties">functionsService</param>
    		</result>
    	</action>

其中functionsService就是不要被JSON序列化的属性。
第二：在Action文件中去除不要被JSON序列化的属性的get()方法，例如：

public IFunctionsService getFunctionsService() {
		return functionsService;
	}

这样做functionsService同样不会被JSON序列化。

说明：
带有transient修饰符与没有Getter方法的字段（field）都不会被串行化为JSON。

评论

3 楼 天枢贪狼 2011-11-02  

感谢楼主 算是帮了大忙 初学json 发现好多不懂

2 楼 bingxue2332 2009-12-17  

ynstudio 写道

		conf.setJsonPropertyFilter(new PropertyFilter(){
		    public boolean apply(Object source, String name, Object value) {
		    	if(source.getClass().getName().indexOf("$$EnhancerByCGLIB$$")>0){
		    		try {
						if(source.getClass().getSuperclass().getField(name) != null)return false;
					} catch (SecurityException e) {
						e.printStackTrace();
					} catch (NoSuchFieldException e) {
						e.printStackTrace();
					}
					return true;
		    	}
		    	return false;
		    }
		});
....
JSONArray jsonArr = JSONArray.fromObject(xxxxx,conf);

我加入了上面的代码但是好像不能生效 ？

1 楼 ynstudio 2009-09-28  

		conf.setJsonPropertyFilter(new PropertyFilter(){
		    public boolean apply(Object source, String name, Object value) {
		    	if(source.getClass().getName().indexOf("$$EnhancerByCGLIB$$")>0){
		    		try {
						if(source.getClass().getSuperclass().getField(name) != null)return false;
					} catch (SecurityException e) {
						e.printStackTrace();
					} catch (NoSuchFieldException e) {
						e.printStackTrace();
					}
					return true;
		    	}
		    	return false;
		    }
		});
....
JSONArray jsonArr = JSONArray.fromObject(xxxxx,conf);