Java 1.1 Unleashed - Appendix C - Java Class Library by Laura Lemay revised by Billy Barron and Jeff Shockley This appendix provides a general overview of the classes available in the standard Java packages (that is, the classes that are guaranteed to be available in any Java implementation). This appendix is intended for general reference; for more specific information about each variable (its inheritance, variables, and methods), as well as the various exceptions for each package, see the API documentation from Sun at http://java.sun.com. A copy of the 1.1 API documentation is on the CD-ROM included with this book. java.lang The java.lang package contains the classes and interfaces that are the core of the Java language. Interfaces Cloneable Interface indicating that an object may be copied or cloned Runnable Methods for classes that want to run as threads Serializable Interface for tagging an object that can be serialized (Java 1.1) Classes Boolean Object wrapper for boolean values Byte Object wrapper for byte values (Java 1.1) Character Object wrapper for char values Class Runtime representations of classes ClassLoader Abstract behavior for handling loading of classes Compiler System class that gives access to the Java compiler Double Object wrapper for double values Float Object wrapper for float values Integer Object wrapper for int values Long Object wrapper for long values Math Utility class for math operations Number Abstract superclass of all number classes (Integer, Float, and so on) Object Generic Object class, at top of inheritance hierarchy Process Abstract behavior for processes such as those spawned using methods in the System class Runtime Access to the Java runtime system SecurityManager Abstract behavior for implementing security policies Short Object wrapper for short values (Java 1.1) String Character strings StringBuffer Mutable strings System Access to Java's system-level behavior, provided in a platform-independent way. Thread Methods for managing threads and classes that run in threads ThreadDeath Class of object thrown when a thread is asynchronously terminated ThreadGroup A group of threads Throwable Generic exception class; all objects thrown must beaThrowable Void Object wrapper for void types (Java 1.1) java.lang.reflect (Java 1.1) The java.lang.reflect package is used to find out information about loaded classes such as what methods and fields they have. Interfaces Member Methods to find out information about a member Classes Array Methods to dynamically create and access arrays Constructor Methods to find out about and access constructors Field Methods to find out about and access variables Method Methods to find out about and access methods Modifier Decoder for static class and member access modifiers java.math (Java 1.1) The java.math package contains two classes that can hold numbers of arbitrary size. Classes BigDecimal A very big floating-point number BigInteger A very big integer number java.util The java.util package contains various utility classes and interfaces, including random numbers, system properties, and other useful classes. Interfaces Enumeration Methods for enumerating sets of values EventListener Methods for listening to events (Java 1.1) Observer Methods for enabling classes to be Observable objects Classes BitSet A set of bits Calendar A generic calendar (Java 1.1) Date The current system date as well as methods for generating and parsing dates Dictionary An abstract class that maps between keys and values (superclass of HashTable) EventObject A event object associated with another object (Java 1.1) GregorianCalendar A Gregorian calendar, which is the type you probably use (Java 1.1) Hashtable A hash table ListResourceBundle A resource supplier for a Locale (Java 1.1) Locale A description of a geographic location (Java 1.1) Observable An abstract class for observable objects Properties A hash table that contains behavior for setting and retrieving persistent properties of the system or a class PropertyResourceBundle A resource supplier which uses properties from a file (Java 1.1) Random Utilities for generating random numbers ResourceBundle A set of objects related to a Locale (Java 1.1) SimpleTimeZone A simplified time zone (Java 1.1) Stack A stack (a last-in-first-out queue) StringTokenizer Utilities for splitting strings into individual "tokens" TimeZone A generic time zone (Java 1.1) Vector A growable array of Objects java.util.zip (Java 1.1) The java.util.zip package provides classes for dealing with ZIP and GZIP files. Interfaces Checksum Methods for calculating a checksum Classes Adler32 Calculates an Adler 32 checksum CRC32 Calculates a CRC 32 checksum CheckedInputStream Input stream with an associated checksum CheckedOutputStream Output stream with an associated checksum Deflator Compressor for uncompressed files DeflatorOutputStream Output stream that compresses files GZIPInputSteam Input stream from a GZIP file GZIPOutputStream Output stream to a GZIP file Inflater Decompressor for compressed files InflaterInputStream Input stream that decompresses files ZipEntry A file entry inside a ZIP file ZipFile A whole ZIP file ZipInputStream Input stream from a ZIP file ZipOutputStream Output stream to a ZIP file java.io The java.io package provides input and output classes and interfaces for streams and files. Interfaces DataInput Methods for reading machine-independent typed input streams DataOutput Methods for writing machine-independent typed output streams Externalizable Methods to write/read an object's contents with a stream (Java 1.1) FilenameFilter Methods for filtering filenames ObjectInput Methods for reading objects (Java 1.1) ObjectInputValidation Methods to validate an object (Java 1.1) ObjectOutput Methods for writing objects (Java 1.1) Serializable Tag to say that this class can be serialized (Java 1.1) Classes BufferedInputStream A buffered input stream BufferedOutputStream A buffered output stream BufferedReader A buffered reader (Java 1.1) BufferedWriter A buffered writer (Java 1.1) ByteArrayInputStream An input stream from a byte array ByteArrayOutputStream An output stream to a byte array CharArrayReader A reader from an array of characters (Java 1.1) CharArrayWriter A writer to an array of characters (Java 1.1) DataInputStream Enables you to read primitive Java types (ints, chars, booleans, and so on) from a stream in a machine-independent way DataOutputStream Enables you to write primitive Java data types (ints, chars, booleans, and so on) to a stream in a machine-independent way File Represents a file on the host's file system FileDescriptor Holds onto the UNIX-like file descriptor of a file or socket FileInputStream An input stream from a file, constructed using a filename or descriptor FileOutputStream An output stream to a file, constructed using a filename or descriptor FileReader A reader from a file, constructed using a filename or descriptor (Java 1.1) FileWriter A writer to a file, constructed using a filename or descriptor (Java 1.1) FilterInputStream Abstract class that provides a filter for input streams (and for adding stream functionality such as buffering) FilterOutputStream Abstract class that provides a filter for output streams (and for adding stream functionality such as buffering) FilterReader A class that provides a filter for readers (and for adding functionality such as buffering) (Java 1.1) FilterWriter A class that provides a filter for writers (and for adding functionality such as buffering) (Java 1.1) InputStream An abstract class representing an input stream of bytes; the parent of all input streams in this package LineNumberInputStream An input stream that keeps track of line numbers ObjectInputStream A class that deserializes data and objects (Java 1.1) ObjectOutputStream A class that serializes data and objects (Java 1.1) ObjectStreamClass A descriptor for classes that can be serialized (Java 1.1) OutputStream An abstract class representing an output stream of bytes; the parent of all output streams in this package OutputStreamWriter A bridge between byte and character streams (Java 1.1) PipedInputStream A piped input stream, which should be connected to a PipedOutputStream to be useful PipedOutputStream A piped output stream, which should be connected to a PipedInputStream to be useful (together they provide safe communication between threads) PipedReader A piped reader, which should be connected to a PipedWriter to be useful (Java 1.1) PipedWriter A piped writer, which should be connected to a PipedReader to be useful (Java 1.1) PrintStream An output stream for printing (used by System.out. println(...)) PrintWriter A writer for printing (Java 1.1) PushbackInputStream An input stream with a pushback buffer PushbackReader A reader with a pushback buffer (Java 1.1) RandomAccessFile Provides random access to a file, constructed from filenames, descriptors, or objects Reader An abstract class representing an input character stream; the parent of all readers in this SequenceInputStream Converts a sequence of input streams into a single input package (Java 1.1) stream StreamTokenizer Converts an input stream into a series of individual tokens StringBufferInputStream An input stream from a String object StringReader A reader from a String object (Java 1.1) StringWriter A writer to a String object (Java 1.1) Writer An abstract class representing an output character stream; the parent of all writers in this package (Java 1.1) java.net The java.net package contains classes and interfaces for performing network operations, such as sockets and URLs. Interfaces ContentHandlerFactory Methods for creating ContentHandler objects FileNameMap Methods for mapping between types (Java 1.1)filenames and MIME SocketImplFactory Methods for creating socket implementations (instance of the SocketImpl class) URLStreamHandlerFactory Methods for creating URLStreamHandler objects Classes ContentHandler Abstract behavior for reading data from a URL connection and constructing the appropriate local object, based on MIME types DatagramPacket A datagram packet (UDP) DatagramSocket A datagram socket DatagramSocketImpl Abstract base class for datagram and multicast sockets (Java 1.1) HttpURLConnection A connection can handle the HTTP protocol (Java 1.1) InetAddress An object representation of an Internet host (host name, IP address) MulticastSocket A server-side socket with support for transmitting data to multiple client sockets (Java 1.1) ServerSocket A server-side socket Socket A socket SocketImpl An abstract class for specific socket implementations URL An object representation of a URL URLConnection Abstract behavior for a socket that can handle various Web-based protocols (http, ftp, and so on) URLEncoder Turns strings into x-www-form-urlencoded format URLStreamHandler Abstract class for managing streams to objects referenced by URLs java.awt The java.awt package contains the classes and interfaces that make up the Abstract Windowing Toolkit. Interfaces Adjustable Methods for objects with adjustable numeric values (Java 1.1) EventSource Methods for objects that generate events (Java 1.1) ItemSelectable Methods for objects that contain a set of selectable items (Java 1.1) LayoutManager Methods for laying out containers LayoutManager2 Methods for laying out containers based on a constraints object (Java 1.1) MenuContainer Methods for menu-related containers PrintGraphics Methods for providing a print graphics context (Java 1.1) Shape Methods for geometric shapes (Java 1.1) Classes AWTEvent The parent of all AWT events (Java 1.1) AWTEventMulticaster A multicast event dispatcher (Java 1.1) BorderLayout A layout manager for arranging items in border formation Button A UI pushbutton Canvas A canvas for drawing and performing other graphics operations CardLayout A layout manager for HyperCard-like metaphors Checkbox A checkbox CheckboxGroup A group of exclusive checkboxes (radio buttons) CheckboxMenuItem A toggle menu item Choice A popup menu of choices Color An abstract representation of a color Component The abstract generic class for all UI components Container Abstract behavior for a component components or containers that can hold other Cursor A screen cursor (Java 1.1) Dialog A window for brief interactions with users Dimension An object representing width and height Event An object representing events caused by the system or based on user input EventQueue A queue of events waiting to be processed (Java 1.1) FileDialog A dialog box for getting filenames from the local file system FlowLayout A layout manager that lays out objects from left to right in rows Font An abstract representation of a font FontMetrics Abstract class for holding information about a specific font's character hapes and height and width information Frame A top-level window with a title Graphics Abstract behavior for representing a graphics context and for drawing and painting shapes and objects GridBagConstraints Constraints for components laid out using GridBagLayout GridBagLayout A layout manager that aligns components horizontally and vertically based on their values from GridBagConstraints GridLayout A layout manager with rows and columns; elements are added to each cell in the grid Image An abstract representation of a bitmap image Insets Distances from the outer border of the window; used to lay out components Label A text label for UI components List A scrolling list MediaTracker A way to keep track of the status of media objects being loaded over the Net Menu A menu that can contain menu items and is a container on a menu bar MenuBar A menu bar (container for menus) MenuComponent The abstract superclass of all menu elements MenuItem An individual menu item MenuShortcut A keyboard shortcut for a menu item (Java 1.1) Panel A container that is displayed Point An object representing a point (x and y coordinates) Polygon An object representing a set of points PopupMenu A menu that pops up (Java 1.1) PrintJob A job to be printed (Java 1.1) Rectangle An object representing a rectangle (x and y coordinates for the top-left corner, plus width and height) ScrollPane A container with automatic scrolling (Java 1.1) Scrollbar A UI scrollbar object SystemColor A class containing the GUI colors for a system (Java 1.1) TextArea A multiline, scrollable, editable text field TextComponent The superclass of all editable text components TextField A fixed-size editable text field Toolkit Abstract behavior for binding the abstract AWT classes to a platform specific toolkit implementation Window A top level window, and the superclass of the Frame and Dialog classes java.awt.datatransfer (Java 1.1) The java.awt.datatransfer package is a subpackage of the AWT that provides interfaces and methods for talking to the clipboard. Interfaces ClipboardOwner Methods for classes providing data to a clipboard Transferable Methods for classes providing data to a transfer operation Classes Clipboard The clipboard itself DataFlavor The opaque concept of a data format StringSelection A transfer agent for a string java.awt.event (Java 1.1) The java.awt.event package is a subpackage of the AWT that implements the new event model for Java 1.1. Interfaces ActionListener Methods for listening to an action event AdjustmentListener Methods for listening to an adjustment event ComponentListener Methods for listening to a component event FocusListener Methods for listening to a focus event ItemListener Methods for listening to an item event KeyListener Methods for listening to a keyboard event MouseListener Methods for listening to a mouse event MouseMotionListener Methods for listening to a mouse motion event TextListener Methods for listening to a text event WindowListener Methods for listening to a window event Classes ActionEvent An action event AdjustmentEvent An adjustment event generated from an adjustable object ComponentAdapter An adapter that listens to component events ComponentEvent A component event ContainerAdapter An adapter that listens to container events ContainerEvent A container event FocusAdapter An adapter that listens to focus events FocusEvent A focus event InputEvent An input event ItemEvent An item event generated from an ItemSelectable object KeyAdapter An adapter that listens to keyboard events KeyEvent A keyboard event MouseAdapter An adapter that listens to mouse events MouseEvent A mouse event MouseMotionAdapter An adapter that listens to mouse motion events, such as drag PaintEvent A component-level paint event TextEvent A text event generated by a TextComponent WindowAdapter An adapter that listens to window events WindowEvent A windowing event xjava.awt.image The java.awt.image package is a subpackage of the AWT that provides interfaces and classes for managing bitmap images. Interfaces ImageConsumer Methods for receiving image data created by an ImageProducer ImageObserver Methods to track the loading and construction of an image ImageProducer Methods for producing image data received by an ImageConsumer Classes AverageScaleFilter A filter that scales an image based on an average algorithm (Java 1.1) ColorModel An abstract class for managing color information for images CropImageFilter A filter for cropping images to a particular size DirectColorModel A specific color model for managing and translating pixel color values FilteredImageSource An ImageProducer that takes an image and an ImageFilter object and produces an image for an ImageConsumer ImageFilter A filter that takes image data from an ImageProducer, modifies it in some way, and hands it off to an ImageConsumer IndexColorModel A specific color model for managing and translating color values in a fixed-color map MemoryImageSource An image producer that gets its image from memory; used after constructing an image by hand PixelGrabber An ImageConsumer that retrieves a subset of the pixels in an image ReplicateScaleFilter A filter that scales an image (Java 1.1) RGBImageFilter Abstract behavior for a filter that modifies the RGB values of pixels in RGB images java.awt.peer The java.awt.peer package is a subpackage of AWT that provides the (hidden) platform- specific AWT classes (for example, Motif, Macintosh, and Windows 95) with platform- independent interfaces to implement. Thus, callers using these interfaces need not know which platform's window system these hidden AWT classes are currently implementing. Each class in the AWT that inherits from either Component or MenuComponent has a corresponding peer class. Each of those classes is the name of the Component with -Peer added (for example, ButtonPeer, DialogPeer, and WindowPeer). Because each one provides similar behavior, they are not enumerated here. java.applet The java.applet package provides applet-specific behavior. Interfaces AppletContext Methods to refer to the applet's context AppletStub Methods for implementing applet viewers AudioClip Methods for playing audio files Classes Applet The base applet class java.beans The java.beans package contains the classes and interfaces that make the JavaBeans technology possible. Interfaces BeanInfo Methods that can be used to find out information explicitly provided by a bean Customizer Methods that define the overhead to provide a complete visual editor for a bean PropertyChangeListener Method that is called when a bound property is changed PropertyEditor Methods that provide support for GUIs that allow users to edit a property value of a given type VetoableChangeListener Methods that are called when a constrained property is changed Visibility Methods used to determine whether interface is available for the bean to use a bean requires a graphical user interface and whether a graphical user Classes BeanDescriptor Provides global information about a bean Beans Provides some general-purpose beans control methods EventSetDescriptor Represents a set of events that a bean is capable of generating FeatureDescriptor Serves as a common base class for the EventSetDescriptor, MethodDescriptor, and PropertyDescriptor classes IndexedPropertyDescriptor Provides methods for accessing the type of an indexed property along with its accessor methods Introspector Provides the overhead necessary to analyze a bean and determine its public properties, methods, and events MethodDescriptor Provides methods for accessing information such as a method's parameters ParameterDescriptor Allows bean implementors to provide additional information for each of their parameters PropertyChangeEvent Stores information relating to a change in a bound or constrained property PropertyChangeSupport A helper class for managing listeners of bound and constrained properties PropertyDescriptor Provides methods for accessing the type of a property along with its accessor methods and describes whether it is bound or constrained PropertyEditorManager Provides a way of registering property types so that their editors can be easily found PropertyEditorSupport A helper class implementing the PropertyEditor interfaces that is used to make the construction of custom property editors a little easier SimpleBeanInfo A support class designed to make it easier for bean developers to provide explicit information about a bean VetoableChangeSupport A helper class for managing listeners of bound and constrained properties java.rmi The java.rmi package contains the classes and interfaces that enable the programmer to create distributed Java-to-Java applications, in which the methods of remote Java objects can be invoked from other Java virtual machines, possibly on different hosts. Interfaces Remote Methods for identifying all remote objects Classes Naming Methods for obtaining references to remote objects based on Uniform Resource Locator (URL) syntax RMISecurityManager Methods defining the RMI stub security policy for applications (not applets) java.rmi.dgc Interfaces DGC Methods for cleaning connections for unused clients Classes Lease Contains a unique VM identifier and a lease duration VMID Methods for maintaining unique VMID across all Java virtual machines java.rmi.registry Interfaces Registry A class used to obtain the registry for different hosts RegistryManager Methods used to interface to the private implementation Classes LocateRegistry Used to obtain the bootstrap for the registry on a particular host java.rmi.server Interfaces LoaderHandler RMIFailureHandler Methods for handling when the RMI runtime system is unable to create a Socket or ServerSocket RemoteCall Methods for implementing calls to a remote object RemoteRef Represents a handle for a remote object ServerRef Represents the server-side handle for a remote object implementation Skeleton Represents the server-side entity that dispatches calls to the actual remote object implementation Unreferenced Methods to receive notification when there are no more remote references to it Classes LogStream Provides a mechanism for logging interest to those monitoring the system errors that are of possible ObjID Used to identify remote objects uniquely in a VM Operation Holds a description of a Java method RMIClassLoader Provides static methods for loading classes over the net-work RMISocketFactory Used by the RMI runtime system to obtain client and server sockets for RMI calls RemoteObject Provides the remote semantics of Object by implementing methods for hashCode, equals, and toString RemoteServer A superclass to all server implementations that provides the framework to support a wide range of remote reference semantics RemoteStub Stub objects are surrogates that support exactly the same set of remote interfaces defined by the actual implementation of the remote object UID Abstraction for creating identifiers that are unique with respect to the the host on which it is generated UnicastRemoteObject Defines a nonreplicated remote object whose references are valid only while the server process is alive java.security The java.security package contains the classes and interfaces that enable the programmer to implement certificates and digital signatures in Java components. Interfaces Certificate Methods for managing a certificate, including encoding and decoding KeyParams An interface to alogrithm-specific key parameter interfaces such as DSAParams Principal Represents the principal component of a certificate Classes DigestInputStream Represents an input stream that has a message digest associated with it DigestOutputStream Represents an output stream that has a message digest associated with it Identity Methods for managing identities, which can be objects such as people, companies, or organizations that can be authenticated using a public key IdentityScope Methods for defining the scope of an identity including the name of the identity, its key, and associated certificates Key An abstract class representing a cryptographic key KeyPair A simple holder for a key pair (a public key and a private key) MessageDigest Methods that provide the functionality of a message digest algorithm PrivateKey A subclass of Key representing a private key Provider Represents a Security Package Provider (SPP) for the Java Security API PublicKey A subclass of Key representing a public key SecureRandom Generates a random number Security Methods for managing Security Package Providers (SPPs) Signature Provides the algorithm for digital signatures Signer Represents an identity that can also sign java.security.acl The java.security.acl package provides the interface to a data structure that guards access to resources. Interfaces Acl An interface representing an Access Control List (ACL), which is a data structure used to guard access to resources AclEntry Methods that allow programmers to add, remove, or set permissions for the Principals of each ACLEntry in the ACL Group Methods that allow programmers to add or remove a member from the group of Principals Owner Represents the owner of an ACL Permission Represents the type of access granted to a resource such as a Principal in the ACL java.security.interfaces Interfaces DSAKey Methods used to authenticate components including Java applets and ActiveX controls distributed on the Web DSAParams Methods allowing programmers to get the base, prime, and subprime DSAPublicKey An interface to a DSA public key java.sql The java.sql package includes classes, interfaces, and methods you can use to connect your Java applications to back-end databases. Interfaces CallableStatement Methods used to execute stored procedures and handle multiple result sets Connection Represents a session with the database DatabaseMetaData An interface allowing information about the database programmers to get high-level Driver Methods used to connect to a database PreparedStatement Methods for running precompiled SQL statements ResultSet Methods for retrieving values from an executed SQL statement ResultSetMetaData Methods that provide properties of the columns in a ResultSet information about the types and Statement Used for static SQL statements Classes Date Provides methods for formatting and referencing date values DriverManager Allows for the managing of a set of JDBC drivers DriverPropertyInfo Provides methods for obtaining different properties of a driver Time Provides methods for formatting and referencing time values Timestamp A wrapper that holds the SQL TIMESTAMP value Types Defines constants that are used to identify SQL types java.text The java.text package includes classes and methods used to format objects such as numbers, dates, times, and so on to a string, or to parse a given string to an object such as number, date, time, and so on. Interfaces CharacterIterator Methods to traverse a string and return various information about it Classes ChoiceFormat Methods that allow the numbers attaching of formats to CollatedString Provides a way to use international strings in a hash table or sorted collection Collation Allows the comparing of Unicode text CollationElementIterator Provides a way to iterate over an international string DateFormat An abstract class that includes several date-time formatting subclasses DateFormatData Methods to set the date-time formatting data DecimalFormat Methods to format numbers Format A base class for all formats FormatStatus Used to align formatted objects MessageFormat Methods to create concatenated messages NumberFormat An abstract class for all number formats including subclasses; you can use their methods to format and parse numbers NumberFormatData Encapsulates localizable number format data ParseStatus Gets the status of parsing when you parse through a string with different formats SimpleDateFormat Methods to format a date or time into a string SortKey Methods to do bitwise comparison of strings StringCharacterIterator Methods for bidirectional iteration over a string TableCollation Implements Collation using data-driven tables TextBoundary Used to locate boundaries in given text

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