a keyword in the Java language, used in the declaration of a class to indicate that a class cannot be instantiated, but can be inherited by other classes. An abstract class can use abstract methods, which don't need to be implemented, but need to be implemented in subclasses

break

A Java keyword, which is used to change the program execution flow and immediately execute from the next sentence of the current statement. If there is a tag after it, the keyword of

case

Java language is executed from the corresponding place of the tag, which is used to define a group of branch choices. If a value is the same as that given in switch, it will be executed from this branch.

catch

a keyword of Java, which is used to declare a block that runs when a run-time error or non-run-time exception occurs in a try statement block.

char

a keyword of Java language, which is used to define a character type

continue

a Java keyword, which is used to interrupt the current loop process and restart execution from the end of the current loop. If there is a tag behind it, execution will start from the corresponding place of the tag.

do

a Java keyword is used to declare a loop. The ending condition of this loop can be set by

double

a Java keyword through the while keyword, which is used to define a variable of double type

else

a Java keyword. if the condition of the if statement is not met, the statement will be executed.

final

a keyword of the Java language. You can only define an entity once, and you can't change it or inherit it later. More strictly speaking, a final-decorated class cannot be subclassed, a final-decorated method cannot be rewritten, and a final-decorated variable cannot change its initial value.

finally

a keyword in Java language, which is used to execute a piece of code regardless of whether there is an exception or runtime error in the previously defined try statement.

float

a Java keyword used to define a floating-point variable

for

a Java keyword used to declare a loop. Programmers can specify statements to loop, deduce conditions and initialize variables.

if

a keyword p>if

Java programming language, which is used to generate a conditional test, and if the condition is true, the statement under if is executed.

Implements

A keyword of the Java (TM) programming language, which is optional in the class declaration and is used to indicate the interface implemented by the current class.

import

a keyword of Java (TM) programming language, which indicates a class or the whole package to be referenced later at the beginning of the source file, so that it is unnecessary to add the name of the package when using it.

instanceof

a Java(TM) keyword with two operands, which is used to test whether the runtime type of the first parameter is compatible with the second parameter.

int

a keyword of Java (TM) is used to define an integer variable

a keyword of Java (TM) is used to define a series of methods and constants. It can be implemented by the class through the implements keyword.

long

a keyword in the Java language, which is used to define a variable of type long.

private

a keyword in the Java language, used in the voice of a method or variable. It means that this method or variable can only be accessed by other elements of this class.

protected

a keyword of Java language, used in the declaration of methods and variables, which means that this method or variable can only be accessed by elements in the same class, subclass or class in the same package.

public

a keyword of Java language, used in the declaration of methods and variables, which indicates that this method or variable can be accessed by elements in other classes.

return

a keyword in Java language, which is used to end the execution of a method. It can be followed by a value required in a method declaration.

short

keyword of Java language, used to define a variable of type short.

static

keyword of Java language, which is used to define a variable as a class variable. A class only maintains a copy of a class variable, no matter how many instances of the class currently exist. "static" can also be used to define a method as a class method. Class methods are called by class names rather than specific instances, and can only manipulate class variables.

this

a keyword of the Java language, which is used to represent an instance of the class in which it appears. This can be used to access class variables and class methods.

throw

keywords in the Java language allow users to throw an exception object or any object that implements throwable.

throws

keywords in the Java language are used in the declaration of the method to explain which exceptions are not handled by this method, but submitted to a higher layer of the program.

transient

keyword of Java language, which is used to indicate that a domain is not part of the serialization of the object. When an object is serialized, the values of transient variables are not included in the serialized representation, but non-transient variables are included.

try

a keyword in the Java language, which is used to define a block that may throw an exception. If an exception is thrown, an optional catch statement block will handle the exception thrown in the try statement block. At the same time, a finally statement block will be executed, whether an exception is thrown or not.

void

keyword of Java language, which is used in the method declaration of Java language to indicate that this method has no return value. "void" can also be used to express a statement without any function.

volatile

a keyword in the Java language, which is used in the declaration of a variable to indicate that the variable is modified asynchronously by several threads running at the same time.

while

a keyword of Java language, which is used to define a repeated loop statement. The exit condition of the loop is part of the while statement.

about break and continue.

the p>continue statement is related to the break statement, but it is seldom used. The continue statement is used to make its for, while or do-while statement start the next loop. In the while and do-while statements, the execution of the continue statement means the immediate execution of the test part; In the for loop statement, the execution of the continue statement means that control is passed to the incremental part.