velocity自定义标签

先看例子

1.先写一个java类，继承org.apache.velocity.runtime.directive.Directive类，重写render方法和getName方法。

　　注：getName方法返回的字符串，就是你的自定义标签，render是渲染方法，获取参数，把相应的页面加载到目标页面等。

package com.thinkgem.jeesite.common.directive;

import java.io.IOException;
import java.io.Writer;

import org.apache.velocity.Template;
import org.apache.velocity.app.VelocityEngine;
import org.apache.velocity.context.InternalContextAdapter;
import org.apache.velocity.exception.MethodInvocationException;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.runtime.directive.Directive;
import org.apache.velocity.runtime.parser.node.Node;
import org.apache.velocity.runtime.parser.node.SimpleNode;
import org.springframework.web.servlet.view.velocity.VelocityConfigurer;

import com.thinkgem.jeesite.modules.sys.utils.SpringContextUtils;

public class TreeselectDirective extends Directive{
    
    private static VelocityConfigurer vc;
    
    public static VelocityEngine ve;
    
    private static void init()
    {
        vc = (VelocityConfigurer) SpringContextUtils.getBean("velocityConfig");
        ve = vc.getVelocityEngine();
    }

    /**
     * 返回标签名
     */
    @Override
    public String getName() {
        // TODO Auto-generated method stub
        return "treeselect";
    }

    /**
     * 类型，分为LINE和BLOCK两种
     */
    @Override
    public int getType() {
        return LINE;
    }

    /**
     * 渲染方法，所有的实现逻辑在这里实现
     */
    @Override
    public boolean render(InternalContextAdapter context, Writer writer,
            Node node) throws IOException, ResourceNotFoundException,
            ParseErrorException, MethodInvocationException 
    {
                //获取参数treeselect(参数一，参数二。。。)
        //id
        SimpleNode idNode = (SimpleNode) node.jjtGetChild(0); 
        String id = (String)idNode.value(context);
        context.put("id", id);
        
        //name
        SimpleNode nameNode = (SimpleNode) node.jjtGetChild(1); 
        String name = (String)nameNode.value(context);
        context.put("name", name);
        
        //value
        SimpleNode valueNode = (SimpleNode) node.jjtGetChild(2); 
        String value = (String)valueNode.value(context);
        context.put("value", value);
        
        //lableName
        SimpleNode lableNameNode = (SimpleNode) node.jjtGetChild(3); 
        String lableName = (String)lableNameNode.value(context);
                //把值传到模版页面
        context.put("lableName", lableName);
        
        //lableValue
        SimpleNode lableValueNode = (SimpleNode) node.jjtGetChild(4); 
        String lableValue = (String)lableValueNode.value(context);
        context.put("lableValue", lableValue);
        
        //title
        SimpleNode titleNode = (SimpleNode) node.jjtGetChild(5); 
        String title = (String)titleNode.value(context);
        context.put("title", title);
        
        //url
        SimpleNode urlNode = (SimpleNode) node.jjtGetChild(6); 
        String url = (String)urlNode.value(context);
        context.put("url", url);
        
        //cssClass
        SimpleNode cssClassNode = (SimpleNode) node.jjtGetChild(7); 
        String cssClass = (String)cssClassNode.value(context);
        context.put("id", id);
        
        //allowClear
        SimpleNode allowClearNode = (SimpleNode) node.jjtGetChild(8); 
        String allowClear = (String)allowClearNode.value(context);
        context.put("cssClass", cssClass);
        
        if(vc==null)
            init();
        try
        {
                        //加载到目标页面的模版页面
            Template template = ve.getTemplate("/directive/sys/treeselect.html");
            template.merge(context, writer);
        } 
        catch (Exception e) 
        {
            e.printStackTrace();
        }
        return true;  
    }
}
    

2.velocity.properties配置

#把所有的java指令类都配置在这里，userdirective这个名字不能改，意思是用户自定义的指令类

userdirective = com.thinkgem.jeesite.common.directive.TreeselectDirective,com.thinkgem.jeesite.common.directive.MessageDirective,com.thinkgem.jeesite.common.directive.TableSortDirective

velocimacro.library.autoreload = true

3.模版页面非常简单，就是一个非常普通的html页面，可以内嵌到目标页面

4.引用：和velocity指令一样

eg：#treeselect("company","company.id",$!{user.company.id},"company.name",$!{user.company.name},"公司","/sys/office/treeData?type=1","input-small","true")

5.注意事项：标签的参数数量一定要和指令类获取的参数数量一样

2016-04-25 09:53:34,744 DEBUG [modules.sys.dao.LogDao.insert] - ==> Parameters: 40493dee35624f64afc2f44b1e7ddb46(String), 2(String), 系统设置-机构用户-用户管理-查看(String), 1(String), 2016-04-25 09:53:34.74(Timestamp), 0:0:0:0:0:0:0:1(String), Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.111 Safari/537.36(String), /jeesite/a/sys/hcuser/list(String), GET(String), (String), java.lang.ArrayIndexOutOfBoundsException: 8
    at org.apache.velocity.runtime.parser.node.SimpleNode.jjtGetChild(SimpleNode.java:183)
    at com.thinkgem.jeesite.common.directive.TreeselectDirective.render(TreeselectDirective.java:97)
    at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:207)
    at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:342)
    at org.apache.velocity.Template.merge(Template.java:356)
    at org.apache.velocity.Template.merge(Template.java:260)
    at org.springframework.web.servlet.view.velocity.VelocityView.mergeTemplate(VelocityView.java:517)
    at org.springframework.web.servlet.view.velocity.VelocityView.doRender(VelocityView.java:462)
    at org.springframework.web.servlet.view.velocity.VelocityView.renderMergedTemplateModel(VelocityView.java:292)
    at org.springframework.web.servlet.view.AbstractTemplateView.renderMergedOutputModel(AbstractTemplateView.java:167)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:267)
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1221)
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1005)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:952)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
    at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
    at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
    at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
    at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
    at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
    at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
    at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
    at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
    at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383)
    at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
    at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:344)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:261)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:620)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Thread.java:745)
(String)
四月 25, 2016 9:53:34 上午 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet springServlet threw exception
java.lang.ArrayIndexOutOfBoundsException: 8
    at org.apache.velocity.runtime.parser.node.SimpleNode.jjtGetChild(SimpleNode.java:183)
    at com.thinkgem.jeesite.common.directive.TreeselectDirective.render(TreeselectDirective.java:97)
    at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:207)
    at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:342)
    at org.apache.velocity.Template.merge(Template.java:356)
    at org.apache.velocity.Template.merge(Template.java:260)
    at org.springframework.web.servlet.view.velocity.VelocityView.mergeTemplate(VelocityView.java:517)
    at org.springframework.web.servlet.view.velocity.VelocityView.doRender(VelocityView.java:462)
    at org.springframework.web.servlet.view.velocity.VelocityView.renderMergedTemplateModel(VelocityView.java:292)
    at org.springframework.web.servlet.view.AbstractTemplateView.renderMergedOutputModel(AbstractTemplateView.java:167)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:267)
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1221)
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1005)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:952)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
    at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
    at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
    at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
    at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
    at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
    at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
    at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
    at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
    at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383)
    at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
    at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:344)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:261)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:620)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Thread.java:745)

2016-04-25 09:53:34,865 ERROR [500.jsp] - Request processing failed; nested exception is java.lang.ArrayIndexOutOfBoundsException: 8
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.ArrayIndexOutOfBoundsException: 8
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:973)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
    at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
    at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
    at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
    at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
    at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
    at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
    at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
    at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
    at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383)
    at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
    at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:344)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:261)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:620)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ArrayIndexOutOfBoundsException: 8
    at org.apache.velocity.runtime.parser.node.SimpleNode.jjtGetChild(SimpleNode.java:183)
    at com.thinkgem.jeesite.common.directive.TreeselectDirective.render(TreeselectDirective.java:97)
    at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:207)
    at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:342)
    at org.apache.velocity.Template.merge(Template.java:356)
    at org.apache.velocity.Template.merge(Template.java:260)
    at org.springframework.web.servlet.view.velocity.VelocityView.mergeTemplate(VelocityView.java:517)
    at org.springframework.web.servlet.view.velocity.VelocityView.doRender(VelocityView.java:462)
    at org.springframework.web.servlet.view.velocity.VelocityView.renderMergedTemplateModel(VelocityView.java:292)
    at org.springframework.web.servlet.view.AbstractTemplateView.renderMergedOutputModel(AbstractTemplateView.java:167)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:267)
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1221)
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1005)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:952)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)

 

总结：

1.继承org.apache.velocity.runtime.directive.Directive类，重写方法

2.配置

3.使用