Java Learning 5--Identifiers and keywords

Identifier:

1. The string sequence used by Java to name elements such as variables, methods, and classes is called an identifier. All the places where you can name them are called identifiers, and you must obey the rules of identifiers.

2. Naming rules for Java identifiers:

Identifiers consist of letters, underscores "_", dollar characters $, or numbers.

Identifiers should begin with a letter, underscore, and dollar symbol.

Java identifiers are case-sensitive and of unlimited length.

Java identifier selection should be noted "see the name" and cannot be the same as the Java keyword.

Key words:

1. Some special meanings are given in Java, and the string used for specialized purposes becomes the keyword (keyword). 2. All Java keywords are lowercase English 3, goto and const although never used, but also be reserved as Java keyword

Java Learning 5--Identifiers and keywords