Java thousand asked _08jdk (003) _JDK Basic Class library have what

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1. What are the JDK base class libraries?

See the Java core Framework here: What is the Java core framework?
The JDK base Class library is divided into two parts, the base library, the extended base library, and provides a considerable amount of functionality, the base library is as follows:

2. lang Packet, Util packet (lang and Util Packages)
   The basic object class, the class class, the string class, the basic type of wrapper class, the basic math class, and so on, are provided by the Lang package.
   The Util package provides basic collection framework, jar processing, and other basic classes.
   Learn about Lang Bao, util package look here: [lang bag, util bag what function][3]

4. Math Package (math)
   The features of the Java Math package include floating-point libraries and arbitrary-precision data operations.
   Learn about the math package here: [What is the function of the Java.util.math package][4]

6. Regulatory Tools (Monitoring and Management)
   The Java platform provides comprehensive monitoring and management tools, including the JVM's regulatory API, regulatory API logs, jconsole and other monitoring tools, Out-of-the-box's regulatory tools (out-of-the-box), Java Management Extension Platform (JMX), and Oracle's platform extensions. The main functions are in the Java.lang.management package.
   Learn about the Java regulatory tools here: [What is the function of the java.lang.management package][5]

8. Package version identification (identification)
   The package version recognition feature enables packages to have multiple versions so that at run time programs and applets can identify specific JRE, JVM, and class package versions.
   Understanding the Java Version Specification look here: [Versioning specification is what][6]

10. referencing objects (Reference Objects)
    Reference objects can interact with the garbage collector to some extent. A program can use reference objects to keep references to other objects so that the latter object can still be collected. You can also specify a period of time after which the collector is notified to determine whether the given object is referenced (accessibility, whether it can be reached) has changed. Reference objects can build a simple cache, refresh the cache when memory utilization is low, and clean up by scheduling this more flexible way. The main functions are in the JAVA.LANG.REF package.
    Learn about referencing objects look here: [Java.lang.ref bag What is the use of][7]

12. Reflection (Reflection)
    Reflection allows Java code to get the fields, methods, and constructors of a class, and can use the reflected fields, methods, and constructors on the basis of security restrictions. The API allows an application to access the public members (fields, methods, constructors) of the target object (based on its runtime Class) or declare a member for a given class.
    See the reflection here: [What Java reflection is][8]

14. Collection Framework (collections framework)
    A set is a collection of objects, and the collection framework is the architecture of a unified management collection that allows different collections to operate independently. The Java Collection framework reduces programming effort while improving performance. It allows for interoperability between unrelated APIs, reduces the cost of designing and learning new APIs, and greatly facilitates the reuse of code.
    See the collection framework here: [What is the Java Collection Framework][9]

16. Concurrency Toolkit (Concurrency Utilities)
    The Concurrency Toolkit provides a powerful, scalable, high-performance multithreaded framework, as well as tools such as thread pooling and blocking queues. This package makes it easy for programmers to do the concurrency work manually, and the main thing is to provide concurrency classes for each collection type of the collection framework. In addition, these packages provide a fool-only tool for concurrent programming. The main function is then java.util.concurrent the package.
    Learn about the Concurrency toolkit look here: [Java.util.concurrent bag What is the use of][10]

18. jar file (Java Archive files)
    The jar (Java Archive) is a platform-independent file format that increases the speed of network transmission, and the jar also supports compression, reducing file size and further improving transmission efficiency. In addition, the author of the applet can add a digital signature to the jar file to achieve the purpose of validating the source. And it is fully extensible, and the corresponding API is in the Java.util.jar package.
    Know the jar look here: what the jar is
    Learn about the Jar file tool here: [Java.util.jar pack what to use][12]

20. Log Tool (Logging)
    The log API is a log report (System Administrator, Field Service engineer, software development team) that provides end users with easy software repair and analysis management. The log API captures a lot of information, such as security failures, configuration errors, performance bottlenecks in applications, and bugs. The main functions are in the java.util.logging package.
    Learn about the Java Log tool here: [java.util.logging bag What to use][13]

22. Configuration Tool (Preferences)
    The Preferences API provides an application with a way to store and retrieve user and system preferences and configuration data. This data is persisted in an implementation-dependent (implementation-dependent) fallback memory (operating system level). Records preferences through two separate trees, one for user preferences and one for System preferences. The main functions are in the Java.util.prefs package.
    Learn about Java preferences here: [What's the Java.util.prefs package for][14]

Java thousand asked _08jdk (003) _JDK Basic Class library have what