# Class Constants

java.lang.Object
org.apache.jasper.Constants

public class Constants extends Object
Some constants and other global data that are used by the compiler and the runtime.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final String`
  `CATALINA_HOME_PROP`
  Name of the system property containing the tomcat product installation path
  `static final int`
  `DEFAULT_BUFFER_SIZE`
  Default size of the JSP buffer.
  `static final int`
  `DEFAULT_TAG_BUFFER_SIZE`
  Default size for the tag buffers.
  `static final String`
  `IE_PLUGIN_URL`
  Deprecated.
  `static final boolean`
  `IS_SECURITY_ENABLED`
  Has security been turned on?
  `static final String`
  `JSP_PACKAGE_NAME`
  The default package name for compiled jsp pages.
  `static final String`
  `JSP_SERVLET_BASE`
  The base class of the generated servlets.
  `static final int`
  `MAX_POOL_SIZE`
  Default tag handler pool size.
  `static final String`
  `NS_PLUGIN_URL`
  Deprecated.
  Will be removed in Tomcat 10.1 onwards
  `static final String`
  `PRECOMPILE`
  The query parameter that causes the JSP engine to just pregenerated the servlet but not invoke it.
  `static final String`
  `SERVICE_METHOD_NAME`
  _jspService is the name of the method that is called by HttpJspBase.service().
  `static final String`
  `SERVLET_CLASSPATH`
  ServletContext attribute for classpath.
  `static final String`
  `SESSION_PARAMETER_NAME`
  The name of the path parameter used to pass the session identifier back and forth with the client.
  `static final String`
  `SPEC_VERSION`
  `static final List<String>`
  `STANDARD_IMPORTS`
  `static final String`
  `TAG_FILE_PACKAGE_NAME`
  The default package name for tag handlers generated from tag files
  `static final String`
  `TEMP_VARIABLE_NAME_PREFIX`
  Prefix to use for generated temporary variable names
  `static final boolean`
  `USE_INSTANCE_MANAGER_FOR_TAGS`
  `static final String`
  `XML_BLOCK_EXTERNAL_INIT_PARAM`
  Name of the ServletContext init-param that determines if the XML parsers will block the resolution of external entities.
  `static final String`
  `XML_VALIDATION_TLD_INIT_PARAM`
  Name of the ServletContext init-param that determines if the XML parsers used for *.tld files will be validating or not.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Constants()`

- ## Method Summary

  ### Methods inherited from class Object

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

- ## Field Details

  - ### SPEC_VERSION

    public static final String SPEC_VERSION
    See Also:
      - Constant Field Values

  - ### JSP_SERVLET_BASE

    public static final String JSP_SERVLET_BASE
    The base class of the generated servlets.

  - ### SERVICE_METHOD_NAME

    public static final String SERVICE_METHOD_NAME
    _jspService is the name of the method that is called by HttpJspBase.service(). This is where most of the code generated from JSPs go.

  - ### STANDARD_IMPORTS

    public static final List<String> STANDARD_IMPORTS

  - ### SERVLET_CLASSPATH

    public static final String SERVLET_CLASSPATH
    ServletContext attribute for classpath. This is tomcat specific. Other servlet engines may choose to support this attribute if they want to have this JSP engine running on them.

  - ### DEFAULT_BUFFER_SIZE

    public static final int DEFAULT_BUFFER_SIZE
    Default size of the JSP buffer.
    See Also:
      - Constant Field Values

  - ### DEFAULT_TAG_BUFFER_SIZE

    public static final int DEFAULT_TAG_BUFFER_SIZE
    Default size for the tag buffers.
    See Also:
      - Constant Field Values

  - ### MAX_POOL_SIZE

    public static final int MAX_POOL_SIZE
    Default tag handler pool size.
    See Also:
      - Constant Field Values

  - ### PRECOMPILE

    public static final String PRECOMPILE
    The query parameter that causes the JSP engine to just pregenerated the servlet but not invoke it.

  - ### JSP_PACKAGE_NAME

    public static final String JSP_PACKAGE_NAME
    The default package name for compiled jsp pages.

  - ### TAG_FILE_PACKAGE_NAME

    public static final String TAG_FILE_PACKAGE_NAME
    The default package name for tag handlers generated from tag files

  - ### NS_PLUGIN_URL

    @Deprecated public static final String NS_PLUGIN_URL
    Deprecated.
    Will be removed in Tomcat 10.1 onwards
    Default URLs to download the plugin for Netscape and IE.
    See Also:
      - Constant Field Values

  - ### IE_PLUGIN_URL

    @Deprecated public static final String IE_PLUGIN_URL
    Deprecated.
    See Also:
      - Constant Field Values

  - ### TEMP_VARIABLE_NAME_PREFIX

    public static final String TEMP_VARIABLE_NAME_PREFIX
    Prefix to use for generated temporary variable names

  - ### IS_SECURITY_ENABLED

    public static final boolean IS_SECURITY_ENABLED
    Has security been turned on?

  - ### USE_INSTANCE_MANAGER_FOR_TAGS

    public static final boolean USE_INSTANCE_MANAGER_FOR_TAGS

  - ### SESSION_PARAMETER_NAME

    public static final String SESSION_PARAMETER_NAME
    The name of the path parameter used to pass the session identifier back and forth with the client.

  - ### CATALINA_HOME_PROP

    public static final String CATALINA_HOME_PROP
    Name of the system property containing the tomcat product installation path
    See Also:
      - Constant Field Values

  - ### XML_VALIDATION_TLD_INIT_PARAM

    public static final String XML_VALIDATION_TLD_INIT_PARAM
    Name of the ServletContext init-param that determines if the XML parsers used for *.tld files will be validating or not.

    This must be kept in sync with org.apache.catalina.Globals

    See Also:
      - Constant Field Values

  - ### XML_BLOCK_EXTERNAL_INIT_PARAM

    public static final String XML_BLOCK_EXTERNAL_INIT_PARAM
    Name of the ServletContext init-param that determines if the XML parsers will block the resolution of external entities.

    This must be kept in sync with org.apache.catalina.Globals

    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### Constants

    public Constants()