# Package org.zkoss.lang

- Interface Summary
  Interface | Description
  --- | ---
  ClassResolver | A resolver that can resolve the class of the given name.
  ContextClassLoaderFactory | An interface to provide a pluggable context class loader, which is used for `Classes.getContextClassLoader(Class)` and `Classes.getContextClassLoaderForName(String)`
  Expectable | A special interface to denote an exception is expectable -- it means the exception is not caused by programming error.

- Class Summary
  Class | Description
  --- | ---
  Classes | Utilities to handle java.lang.Class
  Classes.MethodInfo | The method info class used for `Classes.parseMethod(String signature)`.
  Comparables | Utilities regarding Comparable type objects.
  Exceptions | Utilities for Exceptions.
  Generics | Utilities to handle generic types, such as converting a non-type object to a generic type without warning.
  ImportedClassResolver | The class resolve that allows to import classes and packages, like Java's import statement does.
  Integers | Integer utilities.
  JVMs | Utilities of Java Virtual Machine.
  Library | Represent the scope of ZK libraries.
  Longs | Long relevant utilities.
  MutableInteger | Represents an integer that can be modified.
  Objects | Utilities related to the Object class.
  Primitives | Utilities regarding primitive type and its wrapper class.
  SimpleClassResolver | A simple resolver that depends on `Classes.forNameByThread(java.lang.String)`.
  Strings | String utilities and constants
  Strings.Result | The result of `Strings.substring(java.lang.String, int, char)`.
  SystemException.Aide | Utilities.
  Threads | Thread relevant utilities.

- Exception Summary
  Exception | Description
  --- | ---
  CommonException | The most fundamental non-runtime exception of Potix classes.
  OperationException | The expectable system exception denoting user's operation errors.
  PotentialDeadLockException | Denote a potential dead lock might occur.
  SystemException | Indicates a system exception.