OpenJDK 1.23 · java.lang · APIdia, the JavaDoc alternative

Modifier and Type	Interface and Description
public interface	Appendable An object to which `char` sequences and values can be appended.
public interface	AutoCloseable An object that may hold resources (such as file or socket handles) until it is closed.
public interface	CharSequence A `CharSequence` is a readable sequence of `char` values.
public interface	Cloneable A class implements the `Cloneable` interface to indicate to the `java.lang.Object#clone()` method that it is legal for that method to make a field-for-field copy of instances of that class.
public interface	Comparable< the type of objects that this object may be compared to T> This interface imposes a total ordering on the objects of each class that implements it.
public interface	Iterable< the type of elements returned by the iterator T> Implementing this interface allows an object to be the target of the enhanced `for` statement (sometimes called the "for-each loop" statement).
pack-priv interface	LiveStackFrame UNSUPPORTED This interface is intended to be package-private or move to an internal package.
public interface	ProcessHandle ProcessHandle identifies and provides control of native processes.
public interface	Readable A `Readable` is a source of characters.
public interface	Runnable Represents an operation that does not return a result.

Modifier and Type	Annotation and Description
public @interface	Deprecated A program element annotated `@Deprecated` is one that programmers are discouraged from using.
public @interface	FunctionalInterface An informative annotation type used to indicate that an interface type declaration is intended to be a functional interface as defined by the Java Language Specification.
public @interface	Override Indicates that a method declaration is intended to override a method declaration in a supertype.
public @interface	SafeVarargs A programmer assertion that the body of the annotated method or constructor does not perform potentially unsafe operations on its varargs parameter.
public @interface	SuppressWarnings Indicates the warnings to be suppressed at compile time in the annotated element, and in all elements contained in the annotated element.

Class Summary

Modifier and Type	Class and Description
public class	AbstractMethodError Thrown when an application tries to call an abstract method.
pack-priv abstract class	AbstractStringBuilder A mutable sequence of characters.
pack-priv class	ApplicationShutdownHooks
public class	ArithmeticException Thrown when an exceptional arithmetic condition has occurred.
public class	ArrayIndexOutOfBoundsException Thrown to indicate that an array has been accessed with an illegal index.
public class	ArrayStoreException Thrown to indicate that an attempt has been made to store the wrong type of object into an array of objects.
public class	AssertionError Thrown to indicate that an assertion has failed.
pack-priv class	AssertionStatusDirectives A collection of assertion status directives (such as "enable assertions in package p" or "disable assertions in class c").
pack-priv abstract class	BaseVirtualThread Base class for virtual thread implementations.
public class	Boolean The Boolean class wraps a value of the primitive type `boolean` in an object.
public class	BootstrapMethodError Thrown to indicate that an `invokedynamic` instruction or a dynamic constant failed to resolve its bootstrap method and arguments, or for `invokedynamic` instruction the bootstrap method has failed to provide a call site with a target of the correct method type, or for a dynamic constant the bootstrap method has failed to provide a constant value of the required type.
public class	Byte The `Byte` class wraps a value of primitive type `byte` in an object.
public class	Character The `Character` class wraps a value of the primitive type `char` in an object.
pack-priv abstract class	CharacterData
pack-priv class	CharacterData00 The CharacterData00 class encapsulates the large tables once found in java.lang.Character
pack-priv class	CharacterData01 The CharacterData class encapsulates the large tables once found in java.lang.Character.
pack-priv class	CharacterData02 The CharacterData class encapsulates the large tables found in Java.lang.Character.
pack-priv class	CharacterData03 The CharacterData class encapsulates the large tables found in Java.lang.Character.
pack-priv class	CharacterData0E The CharacterData class encapsulates the large tables found in Java.lang.Character.
pack-priv class	CharacterDataLatin1 The CharacterData class encapsulates the large tables found in Java.lang.Character.
pack-priv class	CharacterDataPrivateUse The CharacterData class encapsulates the large tables found in Java.lang.Character.
pack-priv class	CharacterDataUndefined The CharacterData class encapsulates the large tables found in Java.lang.Character.
pack-priv class	CharacterName
public class	Class< the type of the class modeled by this `Class` object. For example, the type of `String.class` is `Class<String>`. Use `Class<?>` if the class being modeled is unknown. T> Instances of the class `Class` represent classes and interfaces in a running Java application.
public class	ClassCastException Thrown to indicate that the code has attempted to cast an object to a subclass of which it is not an instance.
public class	ClassCircularityError Thrown when the Java Virtual Machine detects a circularity in the superclass hierarchy of a class being loaded.
public class	ClassFormatError Thrown when the Java Virtual Machine attempts to read a class file and determines that the file is malformed or otherwise cannot be interpreted as a class file.
pack-priv class	ClassFrameInfo ClassFrameInfo is an implementation of StackFrame that contains only the class name and declaring class.
public abstract class	ClassLoader A class loader is an object that is responsible for loading classes.
public class	ClassNotFoundException Thrown when an application tries to load in a class through its string name using: The `forName` method in class `Class`. The `findSystemClass` method in class `ClassLoader` . The `loadClass` method in class `ClassLoader`.
public abstract class	ClassValue< the type of the derived value T> Lazily associate a computed value with (potentially) every type.
public class	CloneNotSupportedException Thrown to indicate that the `clone` method in class `Object` has been called to clone an object, but that the object's class does not implement the `Cloneable` interface.
pack-priv class	CompoundEnumeration<E>
pack-priv class	ConditionalSpecialCasing This is a utility class for `String.toLowerCase()` and `String.toUpperCase()`, that handles special casing with conditions.
public class	Double The `Double` class wraps a value of the primitive type `double` in an object.
public abstract class	Enum< The type of the enum subclass E extends Enum<E>> This is the common base class of all Java language enumeration classes.
public class	EnumConstantNotPresentException Thrown when an application tries to access an enum constant by name and the enum type contains no constant with the specified name.
public class	Error An `Error` is a subclass of `Throwable` that indicates serious problems that a reasonable application should not try to catch.
public class	Exception The class `Exception` and its subclasses are a form of `Throwable` that indicates conditions that a reasonable application might want to catch.
public class	ExceptionInInitializerError Signals that an unexpected exception has occurred in a static initializer.
pack-priv class	FdLibm Port of the "Freely Distributable Math Library", version 5.3, from C to Java.
public class	Float The `Float` class wraps a value of primitive type `float` in an object.
public class	IllegalAccessError Thrown if an application attempts to access or modify a field, or to call a method that it does not have access to.
public class	IllegalAccessException An IllegalAccessException is thrown when an application tries to reflectively create an instance (other than an array), set or get a field, or invoke a method, but the currently executing method does not have access to the definition of the specified class, field, method or constructor.
public class	IllegalArgumentException Thrown to indicate that a method has been passed an illegal or inappropriate argument.
public class	IllegalCallerException Thrown to indicate that a method has been called by an inappropriate caller.
public class	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.
public class	IllegalStateException Signals that a method has been invoked at an illegal or inappropriate time.
public class	IllegalThreadStateException Thrown to indicate that a thread is not in an appropriate state for the requested operation.
public class	IncompatibleClassChangeError Thrown when an incompatible class change has occurred to some class definition.
public class	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.
public class	InheritableThreadLocal< the type of the inheritable thread local's value T> This class extends `ThreadLocal` to provide inheritance of values from parent thread to child thread: when a child thread is created, the child receives initial values for all inheritable thread-local variables for which the parent has values.
public class	InstantiationError Thrown when an application tries to use the Java `new` construct to instantiate an abstract class or an interface.
public class	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.
public class	Integer The `Integer` class wraps a value of the primitive type `int` in an object.
public class	InternalError Thrown to indicate some unexpected internal error has occurred in the Java Virtual Machine.
public class	InterruptedException Thrown when a thread is waiting, sleeping, or otherwise occupied, and the thread is interrupted, either before or during the activity.
public class	LayerInstantiationException Thrown when creating a module layer fails.
public class	LinkageError Subclasses of `LinkageError` indicate that a class has some dependency on another class; however, the latter class has incompatibly changed after the compilation of the former class.
pack-priv class	LiveStackFrameInfo
public class	Long The `Long` class wraps a value of the primitive type `long` in an object.
public class	MatchException Thrown to indicate an unexpected failure in pattern matching.
public class	Math The class `Math` contains methods for performing basic numeric operations such as the elementary exponential, logarithm, square root, and trigonometric functions.
public class	Module Represents a run-time module, either `named` or unnamed.
public class	ModuleLayer A layer of modules in the Java virtual machine.
pack-priv class	NamedPackage A NamedPackage represents a package by name in a specific module.
public class	NegativeArraySizeException Thrown if an application tries to create an array with negative size.
public class	NoClassDefFoundError Thrown if the Java Virtual Machine or a `ClassLoader` instance 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.
public class	NoSuchFieldError Thrown if an application tries to access or modify a specified field of an object, and that object no longer has that field.
public class	NoSuchFieldException Signals that the class doesn't have a field of a specified name.
public class	NoSuchMethodError Thrown if an application tries to call a specified method of a class (either static or instance), and that class no longer has a definition of that method.
public class	NoSuchMethodException Thrown when a particular method cannot be found.
public class	NullPointerException Thrown when an application attempts to use `null` in a case where an object is required.
public abstract class	Number The abstract class `Number` is the superclass of platform classes representing numeric values that are convertible to the primitive types `byte`, `double`, `float`, `int`, `long`, and `short`.
public class	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.
public class	Object Class `Object` is the root of the class hierarchy.
public class	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.
public class	Package Represents metadata about a run-time package associated with a class loader.
pack-priv class	PinnedThreadPrinter Helper class to print the virtual thread stack trace when pinned.
public abstract class	Process `Process` provides control of native processes started by ProcessBuilder.start and Runtime.exec.
public class	ProcessBuilder This class is used to create operating system processes.
pack-priv class	ProcessEnvironment
pack-priv class	ProcessHandleImpl ProcessHandleImpl is the implementation of ProcessHandle.
pack-priv class	ProcessImpl java.lang.Process subclass in the UNIX environment.
pack-priv class	PublicMethods A collection of most specific public methods.
public abstract class	Record This is the common base class of all Java language record classes.
public class	ReflectiveOperationException Common superclass of exceptions thrown by reflective operations in core reflection.
public class	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.
public class	RuntimeException `RuntimeException` is the superclass of those exceptions that can be thrown during the normal operation of the Java Virtual Machine.
public class	RuntimePermission This class is for runtime permissions.
public class	ScopedValue< the type of the value T> Preview Third Preview of Scoped Values (JEP 481). A value that may be safely and efficiently shared to methods without using method parameters.
public class	SecurityException Thrown by the security manager to indicate a security violation.
public class	SecurityManager Deprecated for removal since 17. The Security Manager is deprecated and subject to removal in a future release. There is no replacement for the Security Manager. See JEP 411 for discussion and alternatives. The security manager is a class that allows applications to implement a security policy.
public class	Short The `Short` class wraps a value of primitive type `short` in an object.
pack-priv class	Shutdown Package-private utility class containing data structures and logic governing the virtual-machine shutdown sequence.
pack-priv class	StackFrameInfo StackFrameInfo is an implementation of StackFrame that contains the class and method information.
public class	StackOverflowError Thrown when a stack overflow occurs because an application recurses too deeply.
pack-priv class	StackStreamFactory StackStreamFactory class provides static factory methods to get different kinds of stack walker/traverser.
public class	StackTraceElement An element in a stack trace, as returned by `Throwable#getStackTrace()`.
public class	StackWalker A stack walker.
public class	StrictMath The class `StrictMath` contains methods for performing basic numeric operations such as the elementary exponential, logarithm, square root, and trigonometric functions.
public class	String The `String` class represents character strings.
public class	StringBuffer A thread-safe, mutable sequence of characters.
public class	StringBuilder A mutable sequence of characters.
pack-priv class	StringCoding Utility class for string encoding and decoding.
pack-priv class	StringConcatHelper Helper for string concatenation.
public class	StringIndexOutOfBoundsException Thrown by `String` methods to indicate that an index is either negative or greater than the size of the string.
pack-priv class	StringLatin1
pack-priv class	StringUTF16
public class	System The `System` class contains several useful class fields and methods.
pack-priv class	Terminator Package-private utility class for setting up and tearing down platform-specific support for termination-triggered shutdowns.
public class	Thread A thread is a thread of execution in a program.
pack-priv class	ThreadBuilders Defines static methods to create platform and virtual thread builders.
public class	ThreadDeath Deprecated for removal since 20. `Thread#stop()` was originally specified to "stop" a victim thread by causing the victim thread to throw a `ThreadDeath`. An instance of `ThreadDeath` was originally specified to be thrown by a victim thread when "stopped" with `Thread#stop()`.
public class	ThreadGroup A thread group represents a set of threads.
public class	ThreadLocal< the type of the thread local's value T> This class provides thread-local variables.
public class	Throwable The `Throwable` class is the superclass of all errors and exceptions in the Java language.
public class	TypeNotPresentException Thrown when an application tries to access a type using a string representing the type's name, but no definition for the type with the specified name can be found.
public class	UnknownError Thrown when an unknown but serious exception has occurred in the Java Virtual Machine.
public class	UnsatisfiedLinkError Thrown if the Java Virtual Machine cannot find an appropriate native-language definition of a method declared `native`.
public class	UnsupportedClassVersionError Thrown when the Java Virtual Machine attempts to read a class file and determines that the major and minor version numbers in the file are not supported.
public class	UnsupportedOperationException Thrown to indicate that the requested operation is not supported.
public class	VerifyError Thrown when the "verifier" detects that a class file, though well formed, contains some sort of internal inconsistency or security problem.
pack-priv class	VersionProps
public abstract class	VirtualMachineError Thrown to indicate that the Java Virtual Machine is broken or has run out of resources necessary for it to continue operating.
pack-priv class	VirtualThread A thread that is scheduled by the Java virtual machine rather than the operating system.
public class	Void The `Void` class is an uninstantiable placeholder class to hold a reference to the `Class` object representing the Java keyword void.
pack-priv class	WeakPairMap< the type of 1st key in key pair K1, the type of 2nd key in key pair K2, the type of value V> A WeakHashMap-like data structure that uses a pair of weakly-referenced keys with identity equality semantics to associate a strongly-referenced value.
public class	WrongThreadException Thrown to indicate that a method has been called on the wrong thread.

Package java.lang

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Interface Summary

Annotation Summary

Class Summary