# Package org.apache.catalina.util

Class Summary
CharsetMapper: Utility class that attempts to map from a Locale to the corresponding character set to be used for interpreting input text (or generating output text) when the Content-Type header does not include one.
ConcurrentDateFormat: Deprecated. Unused.
ContextName: Utility class to manage context names so there is one place where the conversions between baseName, path and version take place.
CustomObjectInputStream: Custom subclass of `ObjectInputStream` that loads from the class loader for this web application.
DOMWriter: A sample DOM writer.
ErrorPageSupport: Provides support for tracking per exception type and per HTTP status code error pages.
Extension: Utility class that represents either an available "Optional Package" (formerly known as "Standard Extension") as described in the manifest of a JAR file, or the requirement for such an optional package.
ExtensionValidator: Ensures that all extension dependencies are resolved for a WEB application are met.
Introspection: Provides introspection utilities that either require knowledge of Tomcat internals or are solely used by Tomcat internals.
IOTools: Contains commonly needed I/O-related methods
LifecycleBase: Base implementation of the `Lifecycle` interface that implements the state transition rules for `Lifecycle.start()` and `Lifecycle.stop()`
LifecycleMBeanBase
ManifestResource: Representation of a Manifest file and its available extensions and required extensions
MIME2Java: Deprecated. Unused.
NetMask: A class representing a CIDR netmask.
ParameterMap<K,​V>: Implementation of java.util.Map that includes a `locked` property.
RequestUtil: General purpose request parsing and encoding utility methods.
ResourceSet<T>: Extended implementation of HashSet that includes a `locked` property.
ServerInfo: Simple utility module to make it easy to plug in the server identifier when integrating Tomcat.
SessionConfig
SessionIdGeneratorBase
StandardSessionIdGenerator
Strftime: Converts dates to strings using the same format specifiers as strftime Note: This does not mimic strftime perfectly.
SystemPropertyReplacerListener: Deprecated. No longer used.
TLSUtil
TomcatCSS
URLEncoder: This class is very similar to the java.net.URLEncoder class.
XMLWriter: XMLWriter helper class.