# Class Compiler

java.lang.Object
org.apache.jasper.compiler.Compiler

Direct Known Subclasses:
  `AntCompiler, JavaCompiler, JDTCompiler`

public abstract class Compiler extends Object
Main JSP compiler class. This class uses Ant for compiling.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected JspCompilationContext`
  `ctxt`
  `protected ErrorDispatcher`
  `errDispatcher`
  `protected JspServletWrapper`
  `jsw`
  `protected Options`
  `options`
  `protected PageInfo`
  `pageInfo`
  `protected Node.Nodes`
  `pageNodes`
  `protected TagFileProcessor`
  `tfp`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Compiler()`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `compile()`
  Compile the jsp file from the current engine context.
  `void`
  `compile(boolean compileClass)`
  Compile the jsp file from the current engine context.
  `void`
  `compile(boolean compileClass, boolean jspcMode)`
  Compile the jsp file from the current engine context.
  `protected abstract void`
  `generateClass(Map<String, SmapStratum> smaps)`
  Servlet compilation.
  `protected Map<String, SmapStratum>`
  `generateJava()`
  Compile the jsp file into equivalent servlet in .java file
  `JspCompilationContext`
  `getCompilationContext()`
  `ErrorDispatcher`
  `getErrorDispatcher()`
  `PageInfo`
  `getPageInfo()`
  `SmapStratum`
  `getSmap(String className)`
  `void`
  `init(JspCompilationContext ctxt, JspServletWrapper jsw)`
  `boolean`
  `isOutDated()`
  This is a protected method intended to be overridden by subclasses of Compiler.
  `boolean`
  `isOutDated(boolean checkClass)`
  Determine if a compilation is necessary by checking the time stamp of the JSP page with that of the corresponding .class or .java file.
  `void`
  `removeGeneratedClassFiles()`
  `void`
  `removeGeneratedFiles()`
  Remove generated files

  ### Methods inherited from class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### ctxt

    protected JspCompilationContext ctxt

  - ### errDispatcher

    protected ErrorDispatcher errDispatcher

  - ### pageInfo

    protected PageInfo pageInfo

  - ### jsw

    protected JspServletWrapper jsw

  - ### tfp

    protected TagFileProcessor tfp

  - ### options

    protected Options options

  - ### pageNodes

    protected Node.Nodes pageNodes

- ## Constructor Details

  - ### Compiler

    public Compiler()

- ## Method Details

  - ### init

    public void init(JspCompilationContext ctxt, JspServletWrapper jsw)

  - ### getSmap

    public SmapStratum getSmap(String className)

  - ### generateJava

    protected Map<String, SmapStratum> generateJava() throws Exception
    Compile the jsp file into equivalent servlet in .java file
    Returns:
      A map of class names to JSR 045 source maps
    Throws:
      `Exception` - Error generating Java source

  - ### generateClass

    protected abstract void generateClass(Map<String, SmapStratum> smaps) throws FileNotFoundException, JasperException, Exception
    Servlet compilation. This compiles the generated sources into Servlets.
    Parameters:
      `smaps` - The source maps for the class(es) generated from the source file
    Throws:
      `FileNotFoundException` - Source files not found
      `JasperException` - Compilation error
      `Exception` - Some other error

  - ### compile

    public void compile() throws FileNotFoundException, JasperException, Exception
    Compile the jsp file from the current engine context.
    Throws:
      `FileNotFoundException` - Source files not found
      `JasperException` - Compilation error
      `Exception` - Some other error

  - ### compile

    public void compile(boolean compileClass) throws FileNotFoundException, JasperException, Exception
    Compile the jsp file from the current engine context. As a side effect, tag files that are referenced by this page are also compiled.
    Parameters:
      `compileClass` - If true, generate both .java and .class file If false, generate only .java file
    Throws:
      `FileNotFoundException` - Source files not found
      `JasperException` - Compilation error
      `Exception` - Some other error

  - ### compile

    public void compile(boolean compileClass, boolean jspcMode) throws FileNotFoundException, JasperException, Exception
    Compile the jsp file from the current engine context. As a side effect, tag files that are referenced by this page are also compiled.
    Parameters:
      `compileClass` - If true, generate both .java and .class file If false, generate only .java file
      `jspcMode` - true if invoked from JspC, false otherwise
    Throws:
      `FileNotFoundException` - Source files not found
      `JasperException` - Compilation error
      `Exception` - Some other error

  - ### isOutDated

    public boolean isOutDated()
    This is a protected method intended to be overridden by subclasses of Compiler. This is used by the compile method to do all the compilation.
    Returns:
      `true` if the source generation and compilation should occur

  - ### isOutDated

    public boolean isOutDated(boolean checkClass)
    Determine if a compilation is necessary by checking the time stamp of the JSP page with that of the corresponding .class or .java file. If the page has dependencies, the check is also extended to its dependents, and so on. This method can be overridden by a subclasses of Compiler.
    Parameters:
      `checkClass` - If true, check against .class file, if false, check against .java file.
    Returns:
      `true` if the source generation and compilation should occur

  - ### getErrorDispatcher

    public ErrorDispatcher getErrorDispatcher()
    Returns:
      the error dispatcher.

  - ### getPageInfo

    public PageInfo getPageInfo()
    Returns:
      the info about the page under compilation

  - ### getCompilationContext

    public JspCompilationContext getCompilationContext()

  - ### removeGeneratedFiles

    public void removeGeneratedFiles()
    Remove generated files

  - ### removeGeneratedClassFiles

    public void removeGeneratedClassFiles()