# jsp-jstl-engine

**Repository Path**: anyline/jsp-jstl-engine

## Basic Information

- **Project Name**: jsp-jstl-engine
- **Description**: java jsp&jstl template engine
- **Primary Language**: Unknown
- **License**: GPL-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2016-01-17
- **Last Updated**: 2022-06-27

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

java-template
===================

java template jstl

Ayada is a "template engine"; a generic tool to generate text output (anything from HTML to autogenerated source code) based on templates. It's a Java package, a class library for Java programmers. It's not an application for end-users in itself, but something that programmers can embed into their products.

更详细的文档请参考: docs/html/index.html

项目目录结构：
    src - 源码
    release - 最终发布包
    docs/html - 相关文档


Tag Example
===================

c:if

    <c:if test="${1 == 1}">1 == 1</c:if>

out:
    1 == 1

c:forEach & c:each

    <c:forEach items="${1, 2, 3}" var="myvar" varStatus="status">
        ${status.index}: ${myvar}
    </c:forEach>

out:
    0: 1
    1: 2
    2: 3

c:forEach & c:each

    <c:forEach begin="1" end="3" step="1" var="myvar" varStatus="status">
        ${status.index}: ${myvar}
    </c:forEach>

out:
    0: 1
    1: 2
    2: 3

c:forEach & c:each
    var varList = [1, 2, 3];

    <c:forEach items="${varList}" var="myvar" varStatus="status">
        ${status.index}: ${myvar}
    </c:forEach>

out:
    0: 1
    1: 2
    2: 3

c:set

    <c:set var="myvar1" value="${myvar}"/>
    <c:set var="myvar1" value="1,2,3"/>

c:out

    <c:out value="${myvar}" defaultValue="1,2,3" escapeXml="true"/>

out:
    1,2,3

c:choose & c:when & c:otherwise

    <c:choose>
        <c:when test="${userList.length > 6}"><div>test1</div></c:when>
        <c:when test="${userList.length > 7}"><div>test2</div></c:when>
        <c:otherwise><div>test3</div></c:otherwise>
    </c:choose>

c:comment

    <c:comment>
        ...
    </c:comment>

fmt:formatDate

    <fmt:formatDate var="mydate1" value="${mydate}" pattern="yyyy-MM-dd"/>

sql:connect

    <sql:connect var="connection" url="jdbc:mysql://localhost:3306?user=root&password=1234&characterEncoding=utf8" driverClass="com.mysql.jdbc.Driver">
        <sql:execute>...</sql:execute>
        <sql:execute sql="update mytest2 set a=1 where b=1">...</sql:execute>
        <sql:execute file="/user/db/create.sql">...</sql:execute>
    </sql:connect>

sql:execute

    <sql:execute>...</sql:execute>
    <sql:execute sql="update mytest2 set a=1 where b=1">...</sql:execute>
    <sql:execute file="/user/db/create.sql">...</sql:execute>

sql:query

    <sql:query var="resultSet" sql="select * from my_test2 where my_id > 1001" offset="2">...</sql:query>

c:include

    <c:include page="/include/mytest.jsp">
        <c:param name="user" value="${user}"/>
    </c:include>

c:macro

    <c:macro name="myTestMacro">
        <c:param name="user" value="${user}"/>
    </c:macro>

import a tag, scope: current page

t:include

<t:include file="/include/mytest.jsp"/>

include a page

配置说明:
ayada-default.properties

    ayada.compile.source-factory=com.skin.ayada.template.DefaultSourceFactory  # 脚本加载factory, 从文件系统加载
    ayada.compile.source-pattern=jsp,jspf,jspx,tpl                             # 脚本扩展名, 其他类型的文件会被认为是静态文件
    ayada.compile.ignore-jsptag=true                                           # 忽略jsp标签
    ayada.compile.fast-jstl=true                                               # 是否使用fast-jstl

ayada-default.properties

    set util=com.skin.ayada.jstl.util.BeanUtil                                 # 定义一个全局工具类

el表达式转义

    在ayada-default.properties文件中添加一行
    set ELEncoder=com.skin.ayada.jstl.util.HtmlEncoder                         # 对所有的el表达式的输出使用html编码之后再输出

在脚本中输出脚本

有时候我们会希望在脚本中输出脚本, 例如页面中输出一段模板, 这段模板在js中再使用js模板引擎进行渲染, 这中情况下可以使用t:text指令

    <t:text escape="xml">
        <c:if test="${1 == 1}"></c:if>
    </t:text>

t:text标签中的任何内容都会作为静态内容原样输出, 如果escape="xml", 那么其中的内容还会被做html编码
t:text是编译指令，因此转码是在编译期进行的, 以后每次执行都直接输出

API Example
===================

    // demo1
    String sourcePattern = "jsp,jspx";
    String home = "E:\\WorkSpace\\test\\webapp\\template";
    SourceFactory sourceFactory = new DefaultSourceFactory();
    TemplateFactory templateFactory = new TemplateFactory();
    ExpressionFactory expressionFactory = new DefaultExpressionFactory();
    sourceFactory.setHome(home);
    sourceFactory.setSourcePattern(sourcePattern);

    TemplateContext templateContext = new DefaultTemplateContext(home, "UTF-8");
    templateContext.setSourceFactory(sourceFactory);
    templateContext.setTemplateFactory(templateFactory);
    templateContext.setExpressionFactory(expressionFactory);

    StringWriter writer = new StringWriter();
    Template template = templateContext.getTemplate("/test.jsp");
    templateContext.execute(template, new HashMap<String, Object>(), writer);
    System.out.println(writer.toString());


    Source source = new Source("", "<c:out value=\"123\"/>", 0);
    SourceFactory sourceFactory = new MemorySourceFactory(source);
    TagLibrary tagLibrary = TagLibraryFactory.getStandardTagLibrary();
    TemplateCompiler compiler = new TemplateCompiler(sourceFactory);
    compiler.setTagLibrary(tagLibrary);
    Template template = compiler.compile("", "UTF-8");
    StringWriter writer = new StringWriter();

    TemplateContext templateContext = new TemplateContext("");
    PageContext pageContext = JspFactory.getPageContext(templateContext, writer);
    List<User> userList = UserHandler.getUserList(16);
    pageContext.setAttribute("userList", userList);
    DefaultExecutor.execute(template, pageContext);  
    System.out.println(writer.toString()); 

    // demo2
    TemplateContext templateContext = new TemplateContext(home);
    Template template = templateContext.getTemplate(file);
    StringWriter writer = new StringWriter();
    PageContext pageContext = getPageContext(writer);
    DefaultExecutor.execute(template, pageContext);
    System.out.println("-------------- source --------------");
    System.out.println(TemplateUtil.toString(template));
    System.out.println("-------------- result --------------");
    System.out.println(writer.toString());

    // demo3
    SourceFactory sourceFactory = new DefaultSourceFactory("webapp");
    TagLibrary tagLibrary = TagLibraryFactory.getStandardTagLibrary();
    TemplateCompiler compiler = new TemplateCompiler(sourceFactory);
    compiler.setTagLibrary(tagLibrary);

    Template template = compiler.compile("/large.html", "UTF-8");

    StringWriter writer = new StringWriter();
    PageContext pageContext = getPageContext(writer);
    DefaultExecutor.execute(template, pageContext);

    System.out.println("------------- result -------------");
    System.out.println(writer.toString());

    // demo4
    String home = "com/skin/ayada/demo";
    SourceFactory sourceFactory = new ClassPathSourceFactory(home);
    TemplateContext templateContext = new TemplateContext(home);
    templateContext.setSourceFactory(sourceFactory);

    Template template = templateContext.getTemplate("/hello.jsp");
    StringWriter writer = new StringWriter();
    PageContext pageContext = JspFactory.getPageContext(writer);

    System.out.println("-------------- source --------------");
    System.out.println(TemplateUtil.toString(template));

    System.out.println("-------------- System.out.print --------------");
    DefaultExecutor.execute(template, pageContext);

    System.out.println("-------------- result --------------");
    System.out.println(writer.toString());


    <!-- TemplateFilter -->
    <filter>
        <filter-name>TemplateFilter</filter-name>
        <filter-class>com.skin.ayada.filter.TemplateFilter</filter-class>
        <!--
            不同的SourceFactory需要的home路径不同
            DefaultSourceFactory需要home路径必须是绝对路径
            ClassPathSourceFactory需要的home路径必须是包路径
            因此DefaultSourceFactory的home路径需要添加contextPath, TemplateFilter会自动取当前应用的的绝对路径
            ClassPathSourceFactory必须是包路径, TemplateFilter会把此处配置的路径传给ClassPathSourceFactory
        <init-param>
            <param-name>home</param-name>
            <param-value>contextPath:/template</param-value>
        </init-param>
        -->
        <init-param>
            <!--
                模板文件的根路径
                针对不同的SourceFactory这个参数的意义不一样
            -->
            <param-name>home</param-name>
            <param-value>/template</param-value>
        </init-param>
        <init-param>
            <param-name>source-factory</param-name>
            <param-value>com.skin.ayada.source.ClassPathSourceFactory</param-value>
        </init-param>

        <init-param>
            <!--
                默认的TemplateFactory是解释执行
                此处配置不使用默认的TemplateFactory, 而是再次编译为class文件执行
            -->
            <param-name>template-factory</param-name>
            <param-value>com.skin.ayada.template.JspTemplateFactory</param-value>
        </init-param>
        <init-param>
            <!-- 该参数只对JspTemplateFactory生效, 编译之后的class文件的保存目录 -->
            <param-name>jsp-work</param-name>
            <param-value>context: /WEB-INF/ayada</param-value>
        </init-param>
    </filter>

    <!-- filter mapping -->
    <filter-mapping>
        <filter-name>TemplateFilter</filter-name>
        <url-pattern>/template/*</url-pattern>
        <dispatcher>FORWARD</dispatcher>
    </filter-mapping>

java: https://github.com/xuesong123/ayada
javascript: https://github.com/xuesong123/javascript-template