ELInterpreter (Apache Tomcat 8.5.78 API Documentation)

Package org.apache.jasper.compiler

## Interface ELInterpreter

- All Known Implementing Classes:
    `ELInterpreterFactory.DefaultELInterpreter`, `ELInterpreterTagSetters`

      public interface ELInterpreter

  Defines the interface for the expression language interpreter. This allows users to provide custom EL interpreter implementations that can optimise EL processing for an application by , for example, performing code generation for simple expressions.

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `String` | `interpreterCall​(JspCompilationContext context, boolean isTagFile, String expression, Class<?> expectedType, String fnmapvar)` | Returns the string representing the code that will be inserted into the servlet generated for JSP.

- - ### Method Detail

    - #### interpreterCall

          String interpreterCall​(JspCompilationContext context,
                                 boolean isTagFile,
                                 String expression,
                                 Class<?> expectedType,
                                 String fnmapvar)

      Returns the string representing the code that will be inserted into the servlet generated for JSP. The default implementation creates a call to `PageContextImpl.proprietaryEvaluate( String, Class, javax.servlet.jsp.PageContext, org.apache.jasper.runtime.ProtectedFunctionMapper)` but other implementations may produce more optimised code.
      Parameters:
        `context` - The compilation context
        `isTagFile` - `true` if in a tag file rather than a JSP
        `expression` - a String containing zero or more "${}" expressions
        `expectedType` - the expected type of the interpreted result
        `fnmapvar` - Variable pointing to a function map.
      Returns:
        a String representing a call to the EL interpreter.