# Package java.lang

package java.lang

- Related Packages
  Package
  Description
  java.lang.annotation
  java.lang.invoke
  java.lang.ref
  java.lang.reflect
- Class
  Description
  AbstractMethodError
  Exception thrown when an attempt is made to call an abstract method.
  Appendable
  Declares methods to append characters or character sequences.
  ArithmeticException
  Thrown when an exceptional arithmetic condition has occurred.
  ArrayIndexOutOfBoundsException
  Thrown to indicate that an array has been accessed with an illegal index.
  ArrayStoreException
  Thrown to indicate that an attempt has been made to store the wrong type of object into an array of objects.
  AssertionError
  AutoCloseable
  Boolean
  The Boolean class wraps a value of the primitive type boolean in an object.
  Byte
  The Byte class is the standard wrapper for byte values.
  Character
  The Character class wraps a value of the primitive type char in an object.
  CharSequence
  This interface represents an ordered set of characters and defines the methods to probe them.
  Class<T>
  Instances of the class Class represent classes and interfaces in a running Java application.
  ClassCastException
  Thrown to indicate that the code has attempted to cast an object to a subclass of which it is not an instance.
  ClassLoader
  ClassNotFoundException
  Thrown when an application tries to load in a class through its string name using the forName method in class Class but no definition for the class with the specified name could be found.
  Cloneable
  This (empty) interface must be implemented by all classes that wish to support cloning.
  CloneNotSupportedException
  Thrown when a program attempts to clone an object which does not support the `Cloneable` interface.
  Comparable<T>
  This interface should be implemented by all classes that wish to define a
  Deprecated
  An annotation for marking an element as deprecated.
  Double
  The Double class wraps a value of the primitive type double in an object.
  Enum<E extends Enum<E>>
  Implementation class required to compile enums
  Error
  An Error is a subclass of Throwable that indicates serious problems that a reasonable application should not try to catch.
  Exception
  The class Exception and its subclasses are a form of Throwable that indicates conditions that a reasonable application might want to catch.
  Float
  The Float class wraps a value of primitive type float in an object.
  IllegalAccessException
  Thrown when an application tries to load in a class, but the currently executing method does not have access to the definition of the specified class, because the class is not public and in another package.
  IllegalArgumentException
  Thrown to indicate that a method has been passed an illegal or inappropriate argument.
  IllegalMonitorStateException
  Thrown to indicate that a thread has attempted to wait on an object's monitor or to notify other threads waiting on an object's monitor without owning the specified monitor.
  IllegalStateException
  IllegalThreadStateException
  Thrown to indicate that a thread is not in an appropriate state for the requested operation.
  IncompatibleClassChangeError
  `IncompatibleClassChangeError` is the superclass of all classes which represent errors that occur when inconsistent class files are loaded into the same running image.
  IndexOutOfBoundsException
  Thrown to indicate that an index of some sort (such as to an array, to a string, or to a vector) is out of range.
  InstantiationException
  Thrown when an application tries to create an instance of a class using the newInstance method in class Class, but the specified class object cannot be instantiated because it is an interface or is an abstract class.
  Integer
  The Integer class wraps a value of the primitive type int in an object.
  InterruptedException
  Thrown when a thread is waiting, sleeping, or otherwise paused for a long time and another thread interrupts it.
  Iterable<T>
  Objects of classes that implement this interface can be used within a `foreach` statement.
  LinkageError
  `LinkageError` is the superclass of all error classes that occur when loading and linking class files.
  Long
  The Long class wraps a value of the primitive type long in an object.
  Math
  The class Math contains methods for performing basic numeric operations.
  NegativeArraySizeException
  Thrown if an application tries to create an array with negative size.
  NoClassDefFoundError
  Thrown if the Java Virtual Machine tries to load in the definition of a class (as part of a normal method call or as part of creating a new instance using the new expression) and no definition of the class could be found.
  NoSuchFieldError
  Thrown when the virtual machine notices that a program tries to reference, on a class or object, a field that does not exist.
  NullPointerException
  Thrown when an application attempts to use null in a case where an object is required.
  Number
  NumberFormatException
  Thrown to indicate that the application has attempted to convert a string to one of the numeric types, but that the string does not have the appropriate format.
  Object
  Class Object is the root of the class hierarchy.
  OutOfMemoryError
  Thrown when the Java Virtual Machine cannot allocate an object because it is out of memory, and no more memory could be made available by the garbage collector.
  Override
  An annotation to indicate that a method is intended to override a superclass method.
  Record
  Base class for Java record types.
  Runnable
  The Runnable interface should be implemented by any class whose instances are intended to be executed by a thread.
  Runtime
  Every Java application has a single instance of class Runtime that allows the application to interface with the environment in which the application is running.
  RuntimeException
  RuntimeException is the superclass of those exceptions that can be thrown during the normal operation of the Java Virtual Machine.
  SafeVarargs
  SecurityException
  Thrown by the system to indicate a security violation.
  Short
  The Short class is the standard wrapper for short values.
  StackTraceElement
  String
  The String class represents character strings.
  StringBuffer
  A string buffer implements a mutable sequence of characters.
  StringBuilder
  A string builder implements a mutable sequence of characters.
  StringIndexOutOfBoundsException
  Thrown by the charAt method in class String and by other String methods to indicate that an index is either negative or greater than or equal to the size of the string.
  SuppressWarnings
  An annotation that indicates a compiler should suppress any warnings of the type specified in the `#value()`.
  System
  The System class contains several useful class fields and methods.
  Thread
  A thread is a thread of execution in a program.
  ThreadLocal<T>
  Throwable
  The Throwable class is the superclass of all errors and exceptions in the Java language.
  UnsupportedOperationException
  VirtualMachineError
  Thrown to indicate that the Java Virtual Machine is broken or has run out of resources necessary for it to continue operating.
  Void