1. JDK基础说明
版本及新特性获取
作为技术人，关注新技术必不可少，那么最佳的途径。。。看下面。
在 Oracle Java 官方站点有这个非常好的引导地图
官方站点 https://docs.oracle.com/javase/8/
主要的几点
Java 官方学习路线
Java Tutorials Learning Paths
在接下来的文章中我会按照官方推荐路线进行分析源码和思维导图（客户端的我就不关注了^_^，感兴趣的小伙伴自己去理解和分析源码吧）。
为了更好地理解和分析源码，我们来看下Java™平台标准版的API规范中对每个包的说明。
在这里同样我会省略和客户端开发相关的数据。
| Package | Description | 我的说明 |
|---|---|---|
| java.beans | Contains classes related to developing beans -- components based on the JavaBeans™ architecture. | OK |
| java.beans.beancontext | Provides classes and interfaces relating to bean context. | OK |
| java.io | Provides for system input and output through data streams, serialization and the file system. | OK |
| java.lang | Provides classes that are fundamental to the design of the Java programming language. | OK |
| java.lang.annotation | Provides library support for the Java programming language annotation facility. | OK |
| java.lang.instrument | Provides services that allow Java programming language agents to instrument programs running on the JVM. | OK |
| java.lang.invoke | The java.lang.invoke package contains dynamic language support provided directly by the Java core class libraries and virtual machine. | OK |
| java.lang.management | Provides the management interfaces for monitoring and management of the Java virtual machine and other components in the Java runtime. | OK |
| java.lang.ref | Provides reference-object classes, which support a limited degree of interaction with the garbage collector. | OK |
| java.lang.reflect | Provides classes and interfaces for obtaining reflective information about classes and objects. | 反射是框架的核心，精通必不可少。 |
| java.math | Provides classes for performing arbitrary-precision integer arithmetic (BigInteger) and arbitrary-precision decimal arithmetic (BigDecimal). | OK |
| java.net | Provides the classes for implementing networking applications. | OK |
| java.nio | Defines buffers, which are containers for data, and provides an overview of the other NIO packages. | OK |
| java.nio.channels | Defines channels, which represent connections to entities that are capable of performing I/O operations, such as files and sockets; defines selectors, for multiplexed, non-blocking I/O operations. | OK |
| java.nio.channels.spi | Service-provider classes for the java.nio.channels package. | OK |
| java.nio.charset | Defines charsets, decoders, and encoders, for translating between bytes and Unicode characters. | OK |
| java.nio.charset.spi | Service-provider classes for the java.nio.charset package. | OK |
| java.nio.file | Defines interfaces and classes for the Java virtual machine to access files, file attributes, and file systems. | OK |
| java.nio.file.attribute | Interfaces and classes providing access to file and file system attributes. | OK |
| java.nio.file.spi | Service-provider classes for the java.nio.file package. | OK |
| java.rmi | Provides the RMI package. | OK |
| java.rmi.activation | Provides support for RMI Object Activation. | OK |
| java.rmi.dgc | Provides classes and interface for RMI distributed garbage-collection (DGC). | OK |
| java.rmi.registry | Provides a class and two interfaces for the RMI registry. | OK |
| java.rmi.server | Provides classes and interfaces for supporting the server side of RMI. | OK |
| java.security | Provides the classes and interfaces for the security framework. | OK |
| java.security.acl | The classes and interfaces in this package have been superseded by classes in the java.security package. | 已被 java.security 包替代 |
| java.security.cert | Provides classes and interfaces for parsing and managing certificates, certificate revocation lists (CRLs), and certification paths. | OK |
| java.security.interfaces | Provides interfaces for generating RSA (Rivest, Shamir and Adleman AsymmetricCipher algorithm) keys as defined in the RSA Laboratory Technical Note PKCS#1, and DSA (Digital Signature Algorithm) keys as defined in NIST's FIPS-186. | OK |
| java.security.spec | Provides classes and interfaces for key specifications and algorithm parameter specifications. | OK |
| java.sql | Provides the API for accessing and processing data stored in a data source (usually a relational database) using the JavaTM programming language. | OK |
| java.text | Provides classes and interfaces for handling text, dates, numbers, and messages in a manner independent of natural languages. | OK |
| java.text.spi | Service provider classes for the classes in the java.text package. | OK |
| java.time | The main API for dates, times, instants, and durations. | OK |
| java.time.chrono | Generic API for calendar systems other than the default ISO. | OK |
| java.time.format | Provides classes to print and parse dates and times. | OK |
| java.time.temporal | Access to date and time using fields and units, and date time adjusters. | OK |
| java.time.zone | Support for time-zones and their rules. | OK |
| java.util | Contains the collections framework, legacy collection classes, event model, date and time facilities, internationalization, and miscellaneous utility classes (a string tokenizer, a random-number generator, and a bit array). | 这个家伙厉害，重要的集合框架都在这里 |
| java.util.concurrent | Utility classes commonly useful in concurrent programming. | 这个前缀的家伙更厉害，高并发控制，中间件开发必须精通 |
| java.util.concurrent.atomic | A small toolkit of classes that support lock-free thread-safe programming on single variables. | OK |
| java.util.concurrent.locks | Interfaces and classes providing a framework for locking and waiting for conditions that is distinct from built-in synchronization and monitors. | OK |
| java.util.function | Functional interfaces provide target types for lambda expressions and method references. | OK |
| java.util.jar | Provides classes for reading and writing the JAR (Java ARchive) file format, which is based on the standard ZIP file format with an optional manifest file. | OK |
| java.util.logging | Provides the classes and interfaces of the JavaTM 2 platform's core logging facilities. | OK |
| java.util.prefs | This package allows applications to store and retrieve user and system preference and configuration data. | OK |
| java.util.regex | Classes for matching character sequences against patterns specified by regular expressions. | OK |
| java.util.spi | Service provider classes for the classes in the java.util package. | OK |
| java.util.stream | Classes to support functional-style operations on streams of elements, such as map-reduce transformations on collections. | OK |
| java.util.zip | Provides classes for reading and writing the standard ZIP and GZIP file formats. | OK |
| javax.annotation | 略 | OK |
| javax.annotation.processing | Facilities for declaring annotation processors and for allowing annotation processors to communicate with an annotation processing tool environment. | OK |
| javax.lang.model | Classes and hierarchies of packages used to model the Java programming language. | OK |
| javax.lang.model.element | Interfaces used to model elements of the Java programming language. | OK |
| javax.lang.model.type | Interfaces used to model Java programming language types. | OK |
| javax.lang.model.util | Utilities to assist in the processing of program elements and types. | OK |
| javax.management | Provides the core classes for the Java Management Extensions. | OK |
| javax.management.loading | Provides the classes which implement advanced dynamic loading. | OK |
| javax.management.modelmbean | Provides the definition of the ModelMBean classes. | OK |
| javax.management.monitor | Provides the definition of the monitor classes. | OK |
| javax.management.openmbean | Provides the open data types and Open MBean descriptor classes. | OK |
| javax.management.relation | Provides the definition of the Relation Service. | OK |
| javax.management.remote | Interfaces for remote access to JMX MBean servers. | OK |
| javax.management.remote.rmi | The RMI connector is a connector for the JMX Remote API that uses RMI to transmit client requests to a remote MBean server. | OK |
| javax.management.timer | Provides the definition of the Timer MBean. | OK |
| javax.naming | Provides the classes and interfaces for accessing naming services. | OK |
| javax.naming.directory | Extends the javax.naming package to provide functionality for accessing directory services. | OK |
| javax.naming.event | Provides support for event notification when accessing naming and directory services. | OK |
| javax.naming.ldap | Provides support for LDAPv3 extended operations and controls. | OK |
| javax.net | Provides classes for networking applications. | OK |
| javax.net.ssl | Provides classes for the secure socket package. | OK |
| javax.print | Provides the principal classes and interfaces for the JavaTM Print Service API. | OK |
| javax.print.attribute | Provides classes and interfaces that describe the types of JavaTM Print Service attributes and how they can be collected into attribute sets. | OK |
| javax.print.attribute.standard | Package javax.print.attribute.standard contains classes for specific printing attributes. | OK |
| javax.print.event | Package javax.print.event contains event classes and listener interfaces. | OK |
| javax.rmi | Contains user APIs for RMI-IIOP. | OK |
| javax.rmi.CORBA | Contains portability APIs for RMI-IIOP. | OK |
| javax.rmi.ssl | Provides implementations of RMIClientSocketFactory and RMIServerSocketFactory over the Secure Sockets Layer (SSL) or Transport Layer Security (TLS) protocols. | OK |
| javax.script | The scripting API consists of interfaces and classes that define Java TM Scripting Engines and provides a framework for their use in Java applications. | OK |
| javax.security.auth | This package provides a framework for authentication and authorization. | OK |
| javax.security.auth.callback | This package provides the classes necessary for services to interact with applications in order to retrieve information (authentication data including usernames or passwords, for example) or to display information (error and warning messages, for example). | OK |
| javax.security.auth.kerberos | This package contains utility classes related to the Kerberos network authentication protocol. | OK |
| javax.security.auth.login | This package provides a pluggable authentication framework. | OK |
| javax.security.auth.spi | This package provides the interface to be used for implementing pluggable authentication modules. | OK |
| javax.security.auth.x500 | This package contains the classes that should be used to store X500 Principal and X500 Private Credentials in a Subject. | OK |
| javax.security.cert | Provides classes for public key certificates. | OK |
| javax.security.sasl | Contains class and interfaces for supporting SASL. | OK |
| javax.sql | Provides the API for server side data source access and processing from the JavaTM programming language. | OK |
| javax.sql.rowset | Standard interfaces and base classes for JDBC RowSet implementations. | OK |
| javax.sql.rowset.serial | Provides utility classes to allow serializable mappings between SQL types and data types in the Java programming language. | OK |
| javax.sql.rowset.spi | The standard classes and interfaces that a third party vendor has to use in its implementation of a synchronization provider. | OK |
| javax.tools | Provides interfaces for tools which can be invoked from a program, for example, compilers. | OK |
| javax.transaction | Contains three exceptions thrown by the ORB machinery during unmarshalling. | OK |
| javax.transaction.xa | Provides the API that defines the contract between the transaction manager and the resource manager, which allows the transaction manager to enlist and delist resource objects (supplied by the resource manager driver) in JTA transactions. | OK |
| javax.xml | 略 | OK |
| org.w3c.dom | 略 | OK |
参考资料
原创声明
作者：随风浮云
出处：http://www.cnblogs.com/ljmatlight
本文版权归作者所有，欢迎转载，但未经作者同意必须保留此段声明。
文中有不妥或者错误的地方，欢迎勘误，如果你有更好的建议，可以给我留言讨论，共同进步。
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