Java Language: Difference between revisions
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=Variables= | =Variables= | ||
A variable is a ''storage location'' and has an associated type - the compile-time type - that is either a [[#Primitive_Types|primitive type]] or a [[# | A variable is a ''storage location'' and has an associated type - the compile-time type - that is either a [[#Primitive_Types|primitive type]] or a [[#Reference_Types|reference type]]. | ||
=Expressions= | =Expressions= |
Revision as of 19:21, 22 March 2018
Internal
Lexical Structure
Keywords
Statements
synchronized
The synchronized statement acquires a mutual-exclusion lock on behalf of the executing thread, executes a block, then releases the lock. While the executing thread owns the log, no other thread may acquire the lock.
synchronized (expression) block
The type of expression must be a reference type.
Also see:
Modifiers
Method Modifiers
synchronized
A synchronized class method synchronizes on the monitor associated with the Class object of that class.
A synchronized instance method synchronizes on the monitor associated with this - the object instance it is invoked onto.
Also see:
default
Literals
Operators
Types
Java is a statically typed language, which means that every variable and every expression has a type that is known at compile time.
Java is strongly typed language, because the types limit the values a variable can hold or that an expression can produce, limit the operations supported by those types and determine the meaning of operations.
Primitive Types
Reference Types
There are four kinds of reference types: class types, interface types, type variables and array types.
Class Types
Interface Types
Type Variables
Array Types
Values
Variables
A variable is a storage location and has an associated type - the compile-time type - that is either a primitive type or a reference type.
Expressions
Interface
An interface groups related methods together into a contract.
Class
Anonymous Class
Can be used for behavior parameterization.