U

UCS transformation format 8-bit form (UTF-8), Text Encoding, Character Encoders and Decoders, Glossary

UDP (User Datagram Protocol), Sockets, Datagram Sockets, Glossary

UIManager class, Pluggable Look-and-Feel

ulp() method, Floating-Point Components

UnavailableException, ServletExceptions

unbounded wildcard (?), Wildcards, Thinking Outside the Container, <?>, <Object>, and the Raw Type

unboxing, Primitive Types, Autoboxing and Unboxing of Primitives–Performance implications of boxing, Glossary

uncaughtException() method, Uncaught Exceptions

UncaughtExceptionHandler, Uncaught Exceptions

unchecked exceptions, Checked and Unchecked Exceptions–Checked and Unchecked Exceptions

undoableEdit-Happened() method, Event Summary

UnicastRemoteObject class, Exporting remote objects, An RMI Example

Unicode character set, Text Encoding, Glossary

Uniform Resource Identifier (URI), URLs, URNs, and URIs–URLs, URNs, and URIs, Namespaces

Uniform Resource Locators (URLs), Uniform Resource Locators (URLs)–Uniform Resource Locators (URLs), URLs, URNs, and URIs–URLs, URNs, and URIs, URL Pattern Mappings–URL Pattern Mappings

Uniform Resource Names (URNs), URLs, URNs, and URIs–URLs, URNs, and URIs

Unix Network Programming, Sockets

UnknownHostException, The HeartBeat applet code

UnknownServiceException, Stream Data

unlock() method, Locks

Unmarshaller class, Unmarshalling from XML

unnamed package, The unnamed package–The unnamed package

unpack200 command, The pack200 Utility

unreachable objects, Unreachable statements, Garbage Collection

UnsupportedOperationException, Read-Only and Read-Mostly Collections

unsynchronized collections, Synchronizing iterators–Synchronizing iterators, ConcurrentHashMap and ConcurrentLinkedQueue–ConcurrentHashMap and ConcurrentLinkedQueue

ConcurrentHashMap class and ConcurrentLinkedQueue class, ConcurrentHashMap and ConcurrentLinkedQueue–ConcurrentHashMap and ConcurrentLinkedQueue

synchronizing iterators, Synchronizing iterators–Synchronizing iterators

update() method, The Big Picture, The Big Picture

updateComponentTreeUI() method, Pluggable Look-and-Feel

upper bound, Raw Types

URI (Uniform Resource Identifier), URLs, URNs, and URIs–URLs, URNs, and URIs, Namespaces

URI class, Standard types

URL class, Stream Data–Stream Data, Getting the Content as an Object–Getting the Content as an Object, Managing Connections–Managing Connections, Handlers in Practice, Useful Handler Frameworks–Useful Handler Frameworks, Talking to Web Applications, URLs, URNs, and URIs

getting content as object, Getting the Content as an Object–Getting the Content as an Object

handlers in practice, Handlers in Practice

managing connections, Managing Connections–Managing Connections

streaming data, Stream Data–Stream Data

useful handler frameworks, Useful Handler Frameworks–Useful Handler Frameworks

url property, System Properties

<url-pattern> element, URL Pattern Mappings, Servlet Filters

URLConnection class, Managing Connections

URLEncoder class class, Using the GET Method

urlPatterns attribute, Configuration with web.xml and Annotations, Declaring and Mapping Filters

URLs (Uniform Resource Locators), Uniform Resource Locators (URLs)–Uniform Resource Locators (URLs), URLs, URNs, and URIs–URLs, URNs, and URIs, URL Pattern Mappings–URL Pattern Mappings

URNs (Uniform Resource Names), URLs, URNs, and URIs–URLs, URNs, and URIs

useLocale() method, Number formats

User Datagram Protocol (UDP), Sockets, Datagram Sockets, Glossary

user preferences, The Preferences API

user session management, User Session Management

<user-data-constraint> element, Secure Data Transport

userNodeForPackage() method, Preferences for Classes

userRoot() method, The Preferences API

users, authenticating, Authenticating Users–Authenticating Users

US_ASCII character set, Character Encoders and Decoders

UTF-16 character set, Character Encoders and Decoders

UTF-16BE character set, Character Encoders and Decoders

UTF-16LE character set, Character Encoders and Decoders

UTF-8 (UCS transformation format 8-bit form), Text Encoding, Character Encoders and Decoders, Glossary

UUID class, Standard types