Movatterモバイル変換


[0]ホーム

URL:


           
Java 2 Platform
Standard Ed. 5.0

Package java.lang

Provides classes that are fundamental to the design of the Javaprogramming language.

See:
          Description

AppendableAn object to whichchar sequences and values can be appended.
CharSequenceACharSequence is a readable sequence ofchar values.
CloneableA class implements theCloneable interface to indicate to theObject.clone() method that it is legal for that method to make a field-for-field copy of instances of that class.
Comparable<T>This interface imposes a total ordering on the objects of each class that implements it.
Iterable<T>Implementing this interface allows an object to be the target of the "foreach" statement.
ReadableAReadable is a source of characters.
RunnableTheRunnable interface should be implemented by any class whose instances are intended to be executed by a thread.
Thread.UncaughtExceptionHandlerInterface for handlers invoked when aThread abruptly terminates due to an uncaught exception.
 

BooleanThe Boolean class wraps a value of the primitive typeboolean in an object.
ByteTheByte class wraps a value of primitive typebyte in an object.
CharacterTheCharacter class wraps a value of the primitive typechar in an object.
Character.SubsetInstances of this class represent particular subsets of the Unicode character set.
Character.UnicodeBlockA family of character subsets representing the character blocks in the Unicode specification.
Class<T>Instances of the classClass represent classes and interfaces in a running Java application.
ClassLoaderA class loader is an object that is responsible for loading classes.
CompilerTheCompiler class is provided to support Java-to-native-code compilers and related services.
DoubleTheDouble class wraps a value of the primitive typedouble in an object.
Enum<E extends Enum<E>>This is the common base class of all Java language enumeration types.
FloatTheFloat class wraps a value of primitive typefloat in an object.
InheritableThreadLocal<T>This class extendsThreadLocal 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.
IntegerTheInteger class wraps a value of the primitive typeint in an object.
LongTheLong class wraps a value of the primitive typelong in an object.
MathThe classMath contains methods for performing basic numeric operations such as the elementary exponential, logarithm, square root, and trigonometric functions.
NumberThe abstract classNumber is the superclass of classesBigDecimal,BigInteger,Byte,Double,Float,Integer,Long, andShort.
ObjectClassObject is the root of the class hierarchy.
PackagePackage objects contain version information about the implementation and specification of a Java package.
ProcessTheProcessBuilder.start() andRuntime.exec methods create a native process and return an instance of a subclass ofProcess that can be used to control the process and obtain information about it.
ProcessBuilderThis class is used to create operating system processes.
RuntimeEvery Java application has a single instance of classRuntime that allows the application to interface with the environment in which the application is running.
RuntimePermissionThis class is for runtime permissions.
SecurityManagerThe security manager is a class that allows applications to implement a security policy.
ShortTheShort class wraps a value of primitive typeshort in an object.
StackTraceElementAn element in a stack trace, as returned byThrowable.getStackTrace().
StrictMathThe classStrictMath contains methods for performing basic numeric operations such as the elementary exponential, logarithm, square root, and trigonometric functions.
StringTheString class represents character strings.
StringBufferA thread-safe, mutable sequence of characters.
StringBuilderA mutable sequence of characters.
SystemTheSystem class contains several useful class fields and methods.
ThreadAthread is a thread of execution in a program.
ThreadGroupA thread group represents a set of threads.
ThreadLocal<T>This class provides thread-local variables.
ThrowableTheThrowable class is the superclass of all errors and exceptions in the Java language.
VoidThe Void class is an uninstantiable placeholder class to hold a reference to the Class object representing the Java keyword void.
 

Thread.StateA thread state.
 

ArithmeticExceptionThrown when an exceptional arithmetic condition has occurred.
ArrayIndexOutOfBoundsExceptionThrown to indicate that an array has been accessed with an illegal index.
ArrayStoreExceptionThrown to indicate that an attempt has been made to store the wrong type of object into an array of objects.
ClassCastExceptionThrown to indicate that the code has attempted to cast an object to a subclass of which it is not an instance.
ClassNotFoundExceptionThrown when an application tries to load in a class through its string name using: TheforName method in classClass.
CloneNotSupportedExceptionThrown to indicate that theclone method in classObject has been called to clone an object, but that the object's class does not implement theCloneable interface.
EnumConstantNotPresentExceptionThrown when an application tries to access an enum constant by name and the enum type contains no constant with the specified name.
ExceptionThe classException and its subclasses are a form ofThrowable that indicates conditions that a reasonable application might want to catch.
IllegalAccessExceptionAn 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.
IllegalArgumentExceptionThrown to indicate that a method has been passed an illegal or inappropriate argument.
IllegalMonitorStateExceptionThrown 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.
IllegalStateExceptionSignals that a method has been invoked at an illegal or inappropriate time.
IllegalThreadStateExceptionThrown to indicate that a thread is not in an appropriate state for the requested operation.
IndexOutOfBoundsExceptionThrown to indicate that an index of some sort (such as to an array, to a string, or to a vector) is out of range.
InstantiationExceptionThrown when an application tries to create an instance of a class using thenewInstance method in classClass, but the specified class object cannot be instantiated because it is an interface or is an abstract class.
InterruptedExceptionThrown when a thread is waiting, sleeping, or otherwise paused for a long time and another thread interrupts it using theinterrupt method in classThread.
NegativeArraySizeExceptionThrown if an application tries to create an array with negative size.
NoSuchFieldExceptionSignals that the class doesn't have a field of a specified name.
NoSuchMethodExceptionThrown when a particular method cannot be found.
NullPointerExceptionThrown when an application attempts to usenull in a case where an object is required.
NumberFormatExceptionThrown 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.
RuntimeExceptionRuntimeException is the superclass of those exceptions that can be thrown during the normal operation of the Java Virtual Machine.
SecurityExceptionThrown by the security manager to indicate a security violation.
StringIndexOutOfBoundsExceptionThrown byString methods to indicate that an index is either negative or greater than the size of the string.
TypeNotPresentExceptionThrown 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.
UnsupportedOperationExceptionThrown to indicate that the requested operation is not supported.
 

AbstractMethodErrorThrown when an application tries to call an abstract method.
AssertionErrorThrown to indicate that an assertion has failed.
ClassCircularityErrorThrown when a circularity has been detected while initializing a class.
ClassFormatErrorThrown 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.
ErrorAnError is a subclass ofThrowable that indicates serious problems that a reasonable application should not try to catch.
ExceptionInInitializerErrorSignals that an unexpected exception has occurred in a static initializer.
IllegalAccessErrorThrown if an application attempts to access or modify a field, or to call a method that it does not have access to.
IncompatibleClassChangeErrorThrown when an incompatible class change has occurred to some class definition.
InstantiationErrorThrown when an application tries to use the Javanew construct to instantiate an abstract class or an interface.
InternalErrorThrown to indicate some unexpected internal error has occurred in the Java Virtual Machine.
LinkageErrorSubclasses ofLinkageError indicate that a class has some dependency on another class; however, the latter class has incompatibly changed after the compilation of the former class.
NoClassDefFoundErrorThrown if the Java Virtual Machine or aClassLoader 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 thenew expression) and no definition of the class could be found.
NoSuchFieldErrorThrown if an application tries to access or modify a specified field of an object, and that object no longer has that field.
NoSuchMethodErrorThrown 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.
OutOfMemoryErrorThrown 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.
StackOverflowErrorThrown when a stack overflow occurs because an application recurses too deeply.
ThreadDeathAn instance ofThreadDeath is thrown in the victim thread when thestop method with zero arguments in classThread is called.
UnknownErrorThrown when an unknown but serious exception has occurred in the Java Virtual Machine.
UnsatisfiedLinkErrorThrown if the Java Virtual Machine cannot find an appropriate native-language definition of a method declarednative.
UnsupportedClassVersionErrorThrown 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.
VerifyErrorThrown when the "verifier" detects that a class file, though well formed, contains some sort of internal inconsistency or security problem.
VirtualMachineErrorThrown to indicate that the Java Virtual Machine is broken or has run out of resources necessary for it to continue operating.
 

DeprecatedA program element annotated @Deprecated is one that programmers are discouraged from using, typically because it is dangerous, or because a better alternative exists.
OverrideIndicates that a method declaration is intended to override a method declaration in a superclass.
SuppressWarningsIndicates that the named compiler warnings should be suppressed in the annotated element (and in all program elements contained in the annotated element).
 

Package java.lang Description

Provides classes that are fundamental to the design of the Javaprogramming language. The most important classes areObject,which is the root of the class hierarchy, andClass, instances ofwhich represent classes at run time.

Frequently it is necessary to represent a value of primitive type asif it were an object. The wrapper classesBoolean,Character,Integer,Long,Float, andDouble serve this purpose. An object of typeDouble,for example, contains a field whose type is double, representing thatvalue in such a way that a reference to it can be stored in a variableof reference type. These classes also provide a number of methods forconverting among primitive values, as well as supporting suchstandard methods as equals and hashCode. TheVoid class is anon-instantiable class that holds a reference to aClass objectrepresening the primitive type void.

The classMath provides commonly used mathematical functions suchas sine, cosine, and square root. The classesString andStringBuffer similarly provide commonly used operations oncharacter strings.

ClassesClassLoader,Process,Runtime,SecurityManager, andSystem provide "system operations"that manage the dynamic loading of classes, creation of external processes,host environment inquiries such as the time of day, and enforcement ofsecurity policies.

ClassThrowable encompasses objects that may be thrown by thethrow statement (§14.16). Subclasses ofThrowable represent errorsand exceptions.

Package Specification

Character Encodings

The specification of thejava.nio.charset.Charset class describes the naming conventions for characterencodings as well as the set of standard encodings that must be supported byevery implementation of the Java platform.

Since:
JDK1.0

           
Java 2 Platform
Standard Ed. 5.0


[8]ページ先頭

©2009-2025 Movatter.jp