自定义标签在迭代时不能绑定多个变量？?报错

@闲.大赋 你好，想跟你请教个问题版本beetl-core-2.0.13.jar：

原来写了自定义迭代标签，需要需要获取迭代的索引值，所有我在变量的里面添加一个bind方法绑定索引值。下面是自定义标签的源代码，

this.bind("zzzz",i);

上面就是绑定索引值的代码

/**
 * 用于遍历多个系统参数
 * @author Administrator
 *
 */
@BeetlName("param")
public class ParamTag extends BaseTag {
	

	public void render() {
		String key = String.valueOf(this.getAttributeValue("type"));
		if(key!=null){
			List<SysParam> sysParams = KgCacheKit.getSysParamsByType(key);
			for (int i = 0; i < sysParams.size(); i++) {
				this.bind(this.args[2].toString(),sysParams.get(i));
				this.bind("zzzz",i);
				this.doBodyRender();
			}
			
		}
	}
	
}

this.bind("zzzz",i);

这行报错

下面是错误信息

2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - >>错误:htmltagvar 位于68行 资源:/public/user/template/set_sign.html
2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - tag执行抛错
2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - 65|					<div class="form-group">
2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - 66|						<label class="col-md-2 control-label required">指定页码</label>
2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - 67|						<div class="col-md-8">
2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - 68|							<#param type="sign.page" ; target>
2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - 69|								 <label class='radio-inline'><input type="radio" name="page" value="${target.code}" ${zzzz ==0?'checked'}> ${target.name} </label>
2014-11-25 18:08:02 625 [http-8089-5] [ERROR]  - 70|							</#param>
java.lang.RuntimeException
	at org.beetl.core.GeneralVarTagBinding.bind(GeneralVarTagBinding.java:105)
	at com.kg.core.beetl.tag.ParamTag.render(ParamTag.java:28)
	at org.beetl.ext.tag.HTMLTagVarBindingWrapper.render(HTMLTagVarBindingWrapper.java:47)
	at org.beetl.core.statement.TagVarBindingStatement.runTag(TagVarBindingStatement.java:54)
	at org.beetl.core.statement.TagStatement.execute(TagStatement.java:87)
	at org.beetl.core.statement.Program.execute(Program.java:70)
	at org.beetl.core.engine.FastRuntimeEngine$FilterProgram.execute(FastRuntimeEngine.java:43)
	at org.beetl.core.Template.renderTo(Template.java:121)
	at org.beetl.core.Template.renderTo(Template.java:87)
	at com.jfinal.ext.beetl.MyWebRender.render(MyWebRender.java:64)
	at com.jfinal.ext.beetl.KgWebBeetlRender.render(KgWebBeetlRender.java:27)
	at com.jfinal.core.ActionHandler.handle(ActionHandler.java:92)
	at com.jfinal.core.JFinalFilter.doFilter(JFinalFilter.java:72)
	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:191)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
	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:291)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
	at java.lang.Thread.run(Thread.java:619)
2014-11-25 18:08:02 640 [http-8089-5] [ERROR]  - /user/template/set_sign/1-20?q_templateid=ce0f209f9c714ead86e3945e718eb132
com.jfinal.render.RenderException: ERROR
	at com.jfinal.ext.beetl.KgWebBeetlRender.render(KgWebBeetlRender.java:31)
	at com.jfinal.core.ActionHandler.handle(ActionHandler.java:92)
	at com.jfinal.core.JFinalFilter.doFilter(JFinalFilter.java:72)
	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:191)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
	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:291)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
	at java.lang.Thread.run(Thread.java:619)
Caused by: ERROR
	at org.beetl.core.statement.TagVarBindingStatement.runTag(TagVarBindingStatement.java:63)
	at org.beetl.core.statement.TagStatement.execute(TagStatement.java:87)
	at org.beetl.core.statement.Program.execute(Program.java:70)
	at org.beetl.core.engine.FastRuntimeEngine$FilterProgram.execute(FastRuntimeEngine.java:43)
	at org.beetl.core.Template.renderTo(Template.java:121)
	at org.beetl.core.Template.renderTo(Template.java:87)
	at com.jfinal.ext.beetl.MyWebRender.render(MyWebRender.java:64)
	at com.jfinal.ext.beetl.KgWebBeetlRender.render(KgWebBeetlRender.java:27)
	... 14 more
Caused by: java.lang.RuntimeException
	at org.beetl.core.GeneralVarTagBinding.bind(GeneralVarTagBinding.java:105)
	at com.kg.core.beetl.tag.ParamTag.render(ParamTag.java:28)
	at org.beetl.ext.tag.HTMLTagVarBindingWrapper.render(HTMLTagVarBindingWrapper.java:47)
	at org.beetl.core.statement.TagVarBindingStatement.runTag(TagVarBindingStatement.java:54)
	... 21 more

页面的html代码如下

<#param type="sign.page" ; target>
								 <label class='radio-inline'><input type="radio" name="page" value="${target.code}" ${zzzz ==0?'checked'}> ${target.name} </label>
							</#param>