Class EvalTag

All Implemented Interfaces:
IterationTag, JspTag, Tag, TryCatchFinally, Serializable

public class EvalTag extends HtmlEscapingAwareTag
The <eval> tag evaluates a Spring expression (SpEL) and either prints the result or assigns it to a variable. Supports the standard JSP evaluation context consisting of implicit variables and scoped attributes.
Attribute Summary
Attribute Required? Runtime Expression? Description
expression true true The expression to evaluate.
htmlEscape false true Set HTML escaping for this tag, as a boolean value. Overrides the default HTML escaping setting for the current page.
javaScriptEscape false true Set JavaScript escaping for this tag, as a boolean value. Default is false.
scope false true The scope for the var. 'application', 'session', 'request' and 'page' scopes are supported. Defaults to page scope. This attribute has no effect unless the var attribute is also defined.
var false true The name of the variable to export the evaluation result to. If not specified the evaluation result is converted to a String and written as output.
Keith Donald, Juergen Hoeller
See Also:
  • Constructor Details

    • EvalTag

      public EvalTag()
  • Method Details

    • setExpression

      public void setExpression(String expression)
      Set the expression to evaluate.
    • setVar

      public void setVar(String var)
      Set the variable name to expose the evaluation result under. Defaults to rendering the result to the current JspWriter.
    • setScope

      public void setScope(String scope)
      Set the scope to export the evaluation result to. This attribute has no meaning unless var is also defined.
    • setJavaScriptEscape

      public void setJavaScriptEscape(boolean javaScriptEscape) throws JspException
      Set JavaScript escaping for this tag, as boolean value. Default is "false".
    • doStartTagInternal

      public int doStartTagInternal() throws JspException
      Description copied from class: RequestContextAwareTag
      Called by doStartTag to perform the actual work.
      Specified by:
      doStartTagInternal in class RequestContextAwareTag
      same as TagSupport.doStartTag
      See Also:
    • doEndTag

      public int doEndTag() throws JspException
      Specified by:
      doEndTag in interface Tag
      doEndTag in class TagSupport