JDK手册

初学Java发现有很多类没有学到，转载了一篇，方便以后使用

1.java.lang

Object 
String 
AbstractStringBuilder 
StringBuffer 
StringBuilder 
Boolean 
Byte 
Double 
Float 
Integer 
Long 
Short
Thread 
ThreadLocal 
Enum 
Throwable 
Error 
Exception 
Class 
ClassLoader 
Compiler 
System 
Package 
Void 

2.java.util

AbstractList 
AbstractMap
AbstractSet 
ArrayList 
LinkedList
HashMap 
Hashtable
HashSet
LinkedHashMap
LinkedHashSet
TreeMap
TreeSet
Vector
Queue
Stack
SortedMap
SortedSet 
Collections
Arrays
Comparator
Iterator
Base64 
Date
EventListener
Random 
SubList 
Timer 
UUID 
WeakHashMap

3、java.util.concurrent

ConcurrentHashMap
Executor
AbstractExecutorService 
ExecutorService 
ThreadPoolExecutor
BlockingQueue
AbstractQueuedSynchronizer
CountDownLatch
FutureTask
Semaphore
CyclicBarrier
CopyOnWriteArrayList 
SynchronousQueue
BlockingDeque 
Callable

4、java.util.concurrent.atomic

AtomicBoolean
AtomicInteger
AtomicLong 
AtomicReference 

5、java.lang.reflect

Field
Method

6、java.lang.annotation

Annotation
Target
Inherited
Retention
Documented
ElementType
Native 
Repeatable

7、java.util.concurrent.locks

Lock 
Condition
ReentrantLock
ReentrantReadWriteLock

8、java.io

File
InputStream
OutputStream
Reader
Writer

9、java.nio

Buffer
ByteBuffer
CharBuffer
DoubleBuffer
FloatBuffer
IntBuffer
LongBuffer
ShortBuffer

10、java.sql

Connection
Driver 
DriverManager 
JDBCType 
ResultSet
Statement 

11、java.net

Socket 
ServerSocket 
URI 
URL
URLEncoder 

原文链接：https://blog.youkuaiyun.com/weixin_40806611/article/details/82217675