taglib 自定义标签

自定义<%@ taglib prefix="cf" uri="http://training.bmcc.com.cn/tld/functions"%> 

就可以根据${cf:proxyConfig('elearning_play')}

实现自定义标签 读取  proxyConfig中的内容，

如果我们使用jsp2，则web.xml使用的是servlet2.4以上的版本。那我们看一下web.xml对应的头文件：

新增的特性是：

<web-app version= "4"
xmlns="http://javasuncom/xml/ns/j2ee"
xmlns:xsi="http://wwwworg/2001/XMLSchema-instance"
xsi:schemaLocation="http://javasuncom/xml/ns/j2ee
http://javasuncom/xml/ns/j2ee/web-app_2_xsd" >
</web-app> 

首先在web.xml中添加如下代码：

 <jsp-config>
        <taglib>
            <taglib-uri>http://training.bmcc.com.cn/tld/functions</taglib-uri>
            <taglib-location>/WEB-INF/customfunction.tld</taglib-location>
        </taglib>
    </jsp-config>

根据上面的

<%@ taglib prefix="cf" uri="http://training.bmcc.com.cn/tld/functions"%> 

得到taglib-location   这里得到的是customfunction.tld 找到如下文件：直接上代码

<?xml version="1.0" encoding="UTF-8" ?>
<taglib xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
    version="2.0">
    <display-name>Custom Functions</display-name>
    <tlib-version>1.1</tlib-version>
    <short-name>cf</short-name>
    <uri>http://training.bmcc.com.cn/tld/functions</uri>
    <function>
        <name>proxyConfig</name>
        <function-class>com.cmbj.training.common.util.ProxyConfigUtil</function-class>
        <function-signature>java.lang.String getProxyURL(java.lang.String)</function-signature>
    </function>
    <function>
        <name>popedomCheck</name>
        <function-class>com.cmbj.training.common.util.PopedomCheckUtil</function-class>
        <function-signature>boolean check(java.util.Map, java.lang.Integer)</function-signature>
    </function>
    <function>
        <name>checkEmployeeJob</name>
        <function-class>com.cmbj.training.common.util.UserJobUtil</function-class>
        <function-signature>boolean checkEmloyeeJob(java.lang.String)</function-signature>
    </function>
    <function>
        <name>checkManager</name>
        <function-class>com.cmbj.training.common.util.UserJobUtil</function-class>
        <function-signature>boolean checkManager(java.lang.String)</function-signature>
    </function>
    <function>
        <name>getValByKey</name>
        <function-class>com.cmbj.training.common.util.ConstantsMapUtil</function-class>
        <function-signature>java.lang.String getValByKey(java.util.Map, java.lang.String)</function-signature>
    </function>
    <function>
        <name>titleFormat</name>
        <function-class>common.base.util.StringUtil</function-class>
        <function-signature>java.lang.String titleFormat(java.lang.String, java.lang.Integer)</function-signature>
    </function>
    <function>
        <name>titleFormat2</name>
        <function-class>common.base.util.StringUtil</function-class>
        <function-signature>java.lang.String titleFormat(java.lang.String, java.lang.Integer, java.lang.String)</function-signature>
    </function>

    <function>
        <name>checkRoleByName</name>
        <function-class>com.bestnet.common.util.RoleUtil</function-class>
        <function-signature>boolean checkRoleByName(java.util.Map, java.lang.String)</function-signature>
    </function>

    <function>
        <name>checkRoleByCode</name>
        <function-class>com.bestnet.common.util.RoleUtil</function-class>
        <function-signature>boolean checkRoleByCode(java.util.Map, java.lang.String)</function-signature>
    </function>
</taglib>

根据name得到 类路径：

<function-class>com.cmbj.training.common.util.ProxyConfigUtil</function-class>

类内容如下：

public class ProxyConfigUtil {

    private static ResourceLoadUtil RESOURCE_LOADUTIL = new ResourceLoadUtil("/proxyConfig.properties");

    private ProxyConfigUtil() {

    }

    public static String getProxyURL(String proxyURLKey, String defaultVal) {
        return RESOURCE_LOADUTIL.getVal(proxyURLKey, defaultVal);
    }

    public static String getProxyURL(String proxyURLKey) {
        return getProxyURL(proxyURLKey, "");
    }

    public static String getProxyParam(String key){
        return RESOURCE_LOADUTIL.getVal(key);
    }

最后得到配置文件，读取内容，得到相应的url内容${cf:proxyConfig('elearning_play')}
elearning_play=http\://***.***.***\:8011

最终完成自定义标签的配置。