1. Adopt 16-bit double-byte character encoding (Unicode) instead of the ASCII code.
2. Class, the first letter of the interface should be capitalized, the first letter of the method should be lowercase.
The first letter of the variable should be lowercase, and the words are segmented by uppercase letters, not available _ and $.
The constant is all uppercase, the word _ segmentation. Object constants can be used in case case.
A single statement in the control structure must also be enclosed with a parentheses.
3. True, false, null in keywords. There is no SizeOF operator. No goto and const.
4. Data types are divided into boolean (16), char (16), string, long (64), int (32), short (16), byte (8), Double (64), float (32). There is also a class type. The difference is that the simultaneous distribution of the simplicity type is allocated, and the statement is not as class type. Before using the class variable, first get new to allocate space. And use data reference, not do anything you can do.
5. The instance variable defines the properties of a particular object instance. Class variables define the properties of the entire class. This variable affects the class itself and all instances of this class. Local variables are temporary variables.
6. The for statement is used for the case where the number of cycles can be predetermined, while the While and DO ... While statements are used to cycle the number of cycles.
7. The declaration of the array is only created, and the actual storage space of the array element is dynamically allocated by the NEW.
8. The number of elements in the array is represented by the Length property.
9. Examples of applying for multidimensional arrays in Java.
Method 1: int Str [] [] = new int [2] [];
Str [0] = new int [5];
STR [1] = new int [4]; // Non-rectangular array
Method 2: int STR [] [] = new int [2] [5]; // Rectangular array
