创建自定义标记时使用 JSTL 核心库失败

Question

所以我正在尝试导入两个标记库：

<%@ taglib uri="MyCustomTagLib" prefix="myLib" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

但是，我只能使用其中的一个，否则会出现错误（我缩短了它，希望没关系）：

WARNING: ApplicationDispatcher[/CSE336_A5] PWC1231: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
    at org.apache.jasper.compiler.TagLibraryInfoImpl.toString(TagLibraryInfoImpl.java:129)
    at java.lang.String.valueOf(String.java:2826)
    at java.lang.StringBuilder.append(StringBuilder.java:115)
    at java.util.AbstractMap.toString(AbstractMap.java:490)
    at org.apache.taglibs.standard.tag.common.core.OutSupport.out(OutSupport.java:211)
    at org.apache.taglibs.standard.tag.common.core.OutSupport.doStartTag(OutSupport.java:132)

WARNING: StandardWrapperValve[FormOutputController]: PWC1406: Servlet.service() for servlet FormOutputController threw exception
java.lang.NullPointerException
    at org.apache.jasper.compiler.TagLibraryInfoImpl.toString(TagLibraryInfoImpl.java:129)
    at java.lang.String.valueOf(String.java:2826)
    at java.lang.StringBuilder.append(StringBuilder.java:115)
    at java.util.AbstractMap.toString(AbstractMap.java:490)
    at org.apache.taglibs.standard.tag.common.core.OutSupport.out(OutSupport.java:211)
    at org.apache.taglibs.standard.tag.common.core.OutSupport.doStartTag(OutSupport.java:132)
    at org.apache.jsp.form_005fdebug_jsp._jspx_meth_c_out_1(form_005fdebug_jsp.java from :266)
    at org.apache.jsp.form_005fdebug_jsp._jspx_meth_c_forEach_0(form_005fdebug_jsp.java from :214)
    at org.apache.jsp.form_005fdebug_jsp._jspService(form_005fdebug_jsp.java from :99)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)

如果我只是将其中一个注释掉，我不会收到任何错误，并且该库可以正常工作。如果我同时使用两者，我会收到此错误。

谢谢

Answer 1

将您的 taglib uri 更改为类似 uri="http://www.example.com/custom_tag_lib"

还可以按如下方式更改您的自定义 tld 属性

custom_tag_lib http://www.example.com/custom_tag_lib