Overview

<expr>
value default

Like <%= ... %> but for EL expressions.

<c:set var="city"         value="$customer.address.city"/>

<c:set var="customerFmt" scope="request">
  <font color=red>
    <c:expr value="$customer"/>
  </font>
</c:set>

<c:set var="city"         value="$customer.address.city"/>

<c:set var="customerFmt" scope="request">
  <font color=red>
    <c:expr value="$customer"/>
  </font>
</c:set>

<declare>
id type

Declares a scripting variable, initially defined by an existing scoped attribute of the same name. The type of the variable defaults to java.lang.Object but can be modified by using the 'type' attribute.

<c:declare id="customer" type="acme.Customer"/>

<forEach>
var items status
begin end step

The basic iteration tag, accepting many different collection types and supporting subsetting and other functionality

<forTokens>
var items status
begin end step
delims

Iterates over tokens, separated by the supplied delimiters

<if>
test var

Simple conditional tag, which evalutes its body if the supplied condition is true and optionally exposes a Boolean page attribute representing the evaluation of this condition.

<c:if test="$customer.address.country == 'USA'">
  ...
</c:if>

<c:if var="isUsCustomer"
  test="$customer.address.country == 'USA'"/>

<choose>
<when>
  test
<otherwise>

Simple conditional tag that establishes a context for mutually exclusive conditional operations, marked by <when> and <otherwise>.

<c:choose>
  <when test="...">
    ...
  </when>
  <when test="...">
    ...
  </when>
  ...
  <otherwise>
    ...
  </otherwise>
</c:choose>

<import>
url var varReader charEncoding context


Action for a simple, generic way to access URL based resources. Extends <jsp:include> to support foreign contexts and absolute URLs, as well as to export an object for explicit collaboration with process/transformation tags (avoiding unnecessary buffering).

<c:import url="ftp://ftp.acme.com/README"/>

<c:import url="/xml/doc.xml" varReader="in"/>
<acme:process in="$in"/>

<param>
name value encode

Sub-element to specify request parameters for the enclosing <import>. The name and value of the parameter are url encoded (unless encode is false).

<c:import url="/exec/register">
  <c:param name="id" value="foo"/>
</c:import>

<urlEncode>
value var

URL encoding.

<a href="http://acme.com/register
   ?name=<c:urlEncode value='$name'/>"/>

<expr>
select

Evaluates the given XPath expression and outputs its text value.

<x:expr select="$ath/name"/>

<set>
var select

Evaluates the given XPath expression and saves the result into the JSP scoped attribute specified by "var".

<if>
 select

Simple conditional tag, which evalutes its body if the supplied Xpath expression evaluates to true (as if by a call to the XPath "boolean" function).

<choose>
<when>
 select
<otherwise>

Simple conditional tag that establishes a context for mutually exclusive conditional operations, marked by <when> and <otherwise>.

<transform>
source xslt transformer result var


Applies a transformation to an XML document given a specific XSLT stylesheet or a transformer object.

<c:import url="/xml/employees.xml" var="xml"/>
<c:import url="/xslt/customerList.xsl" var="xslt"/>
<x:xslt source="$xml" xslt="$xslt"/>

<param>
name value

Sub-element to specify request parameters for the enclosing <transform>.

<x:transform source="$xml" xslt="$xslt">
  <x:param name="foo" value="foo-value"/>
</x:transform>

<transformer>
var xslt

Creates a "transformer" object for more efficient transformations that use the same XSLT stylesheet.

<c:import url="/xslt/style.xsl" var="xslt"/>
<x:transformer xslt="$xslt" var="transformer"/>
...
<x:transform source="$xml" transformer="$transformer" />
...
<x:transform source="$xml2" transformer="$transformer" />

Establishes the locale specified by the value attribute for the variant given by the variant attribute.

Establishes the time zone given by the value attribute.

Loads the resource bundle whose base name is specified by the basename attribute, and optionally exposes it in the named scoped attribute.

Fetches the localized message corresponding to the key specified by the key attribute from the resource bundle given by the bundle attribute, and performs parametric replacement on the retrieved message using the argument values supplied via <messageArg> subtags

Performs parametric replacement on the pattern specified by the value attribute using the argument values supplied via <messageArg> subtags

Supplies the argument specified by the value attribute  (if present) or the tag body to its parent <message> action for parametric replacement

Formats the given numeric value as a number, currency, or percentage using the locale's predefined or the specified (customized) formatting pattern 

Parses the given numeric string using the locale's default or the specified (customized) formatting pattern

Formats the given date using the locale's predefined or the specified (customized) formatting pattern 

Parses the given date string using the locale's default or the specified (customized) formatting pattern

Displays the exception given by the value attribute (or the error page's exception if no value attribute is given) in its localized form

<sql:query>

<sql:query var="varName"
          sql="sqlQuery"
          [dataSource=dataSourceSpec]
          [maxRows="maxRows"]
          [startRow="startRow"]/>

<sql:query var="varName"
          [sql="sqlQuery"]
          [dataSource=dataSourceSpec]
          [maxRows="maxRows"]
          [startRow="startRow"]/>
  ... optional query statement ...
  ... optional <sql:param> actions ...
</sql:query>

General purpose action for performing SQL queries on a database and gettting back a single result set containing rows of data.

<sql:query var="customers"
             dataSource="$dataSource">
   SELECT * FROM employees
   WHERE country = 'China'
   ORDER BY lastname
</sql:query>

<sql:update>

<sql:update var="varName"
          sql="sqlUpdate"
          [dataSource=dataSourceSpec]/>

<sql:update var="varName"
          [sql="sqlUpdate"]
          [dataSource=dataSourceSpec]>
  ... optional query statement ...
  ... optional <sql:param> actions ...
</sql:update>

General purpose action for "updates"; i.e. statements that update the database (insert, update, delete) and return nothing or a single integer.

<sql:update>
  UPDATE account
  SET BALANCE = ?
  WHERE accountNo = ?
  <sql:param
     value="$balance">
  <sql:param
     value="$accountNo">
</sql:update>

<sql:transaction>

<sql:transaction
    [dataSource=dataSourceSpec]
    [transactionIsolation="transactionIsolationLevel"]>
  ... <sql:query> and <sql:update> statements ...
</sql:transaction>

<sql:driver>

<sql:driver var="varName"
           [driver="driverClassName"]
           [url="url"]
           [user="user"] />

Facilitates the setup of a DataSource object around a JDBC driver for prototype/simple applications.

<sql:param>


<sql:param value="parameterValue"/>

<sql:param>
  ... parameter value ...
</sql:param>

Subtag of SQLExecutionTag actions such as <sql:query> and <sql:update> to set the values of parameter markers ('?') specified in the SQL statement.

<sql:query> result related interfaces


public interface Result
public interface ResultMetaData
public interface Row
public interface ColumnMetaData
public interface Column

interface SQLExecutionTag

Identifies a tag handler that can accept parameter values from nested tag handlers.

(Nothing special is required to use the Core TLV. This validator simply does its best to ensure that JSTL's tags are used correctly, reporting useful error messages when it can.)

<%@ taglib prefix="scriptfree"
    uri="http://jakarta.apache.org/taglibs/jsptl/scriptfree" %>

Temporary mechanisms that allow for runtime pluggability of expression-language evaluators. This allows for experimentation with expression languages and is not expected to remain in the final release of JSTL 1.0.

context parameter

Establishes the default Expression Language used by the web application.

<context-param>
  <param-name>
    javax.servlet.jstl.ExpressionEvaluatorClass
  </param-name>
  <param-value>
    org.apache.taglibs.jstl.lang.spel.Evaluator
  </param-value>
</context-param>

<expressionLanguage>

Change the current Expression Language

<c:expressionLanguage
  evaluator="org.apache.taglibs.jstl.lang.jpath.Evaluator">
  ...
</c:expressionLanguage>