Java自定义标签不起作用/使用问题

Question

我在JSP中使用自定义标签存在很大的问题。我已经在WEB-INF / tlds中创建了一个标记库描述符文件，称为“装饰”。我将前缀设置为“ d”。然后，我创建了名为“ decorateHandler”的标签处理程序类。

我想用简单的方法修饰JSP标题页中的文本，但出现错误...

我的decorate.tld文件：

<tlib-version>1.0</tlib-version>
  <short-name>l</short-name>
  <uri>/WEB-INF/tlds/decorate</uri>
  <tag>
    <name>decorate</name>
    <tag-class>decorateHandler</tag-class>
    <body-content>JSP</body-content> 
    <attribute>
        <name>value</name>
    </attribute>
  </tag>
</taglib>

在decorateHandler.java中，我试图这样做：

private String value;

    private void writeTagBodyContent(JspWriter out, BodyContent bodyContent) throws IOException {

        out.println("<font color='"+value+"'>");
        bodyContent.writeOut(out);
        out.println("</font>");

        bodyContent.clearBody();
    }

当然，我已经为String值变量创建了getter和setter。

在index.jsp中，我像这样包含了taglib：

<%@taglib uri="/WEB-INF/tlds/decorate.tld" prefix="d" %>

而且我尝试过这样的事情：

 <d:decorate value="red">Lorem ipsum</d:decorate>

但是我有一个例外：

org.apache.jasper.JasperException: Unable to compile class for JSP: 

An error occurred at line: [112] in the jsp file: [/index.jsp]
decorateHandler cannot be resolved to a type
109:                         <li class="nav-item">
110:                             <a class="nav-link" href="index.jsp">
111:                                 <img src="logo.png" height="20px" width="20px">
112:                                 <d:decorate value="red">Lorem ipsum</d:decorate>
113:                             </a>
114:                         </li>
115:                     </ul>      


An error occurred at line: [112] in the jsp file: [/index.jsp]
decorateHandler cannot be resolved to a type
109:                         <li class="nav-item">
110:                             <a class="nav-link" href="index.jsp">
111:                                 <img src="logo.png" height="20px" width="20px">
112:                                 <d:decorate value="red">Lorem ipsum</d:decorate>
113:                             </a>
114:                         </li>
115:                     </ul>      


An error occurred at line: [112] in the jsp file: [/index.jsp]
The method get(Class<? extends Tag>) in the type TagHandlerPool is not applicable for the arguments (Class<decorateHandler>)
109:                         <li class="nav-item">
110:                             <a class="nav-link" href="index.jsp">
111:                                 <img src="logo.png" height="20px" width="20px">
112:                                 <d:decorate value="red">Lorem ipsum</d:decorate>
113:                             </a>
114:                         </li>
115:                     </ul>      


An error occurred at line: [112] in the jsp file: [/index.jsp]
decorateHandler cannot be resolved to a type
109:                         <li class="nav-item">
110:                             <a class="nav-link" href="index.jsp">
111:                                 <img src="logo.png" height="20px" width="20px">
112:                                 <d:decorate value="red">Lorem ipsum</d:decorate>
113:                             </a>
114:                         </li>
115:                     </ul>      


Stacktrace:
    org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:102)
    org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:212)
    org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:549)
    org.apache.jasper.compiler.Compiler.compile(Compiler.java:378)
    org.apache.jasper.compiler.Compiler.compile(Compiler.java:350)
    org.apache.jasper.compiler.Compiler.compile(Compiler.java:334)
    org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:595)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:399)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    Filtr2.doFilter(Filtr2.java:67)

我不知道是什么问题...：/