Java basic knowledge explanation - enumeration type definition

•JDK1.5After that, you can use the enum keyword to define the enumeration type , the grammatical structure is as follows:

[public] enum Enumeration name[implements Interface list] {

Enumeration object1[, Enumeration object2] [,… ];

[Member variables 1;]

[Member variable2;]

[…]

##[(static or non-static)Code block

[Construction method1]

[Construction method2##]

[…]

#[

Normal method1]

[

Normal method2]

[

…]

[

Abstract method1]

[

Abstract method2]

[

…]## }

public enum Color {

	RED(1, "红色"), GREEN(2, "绿色"), BLUE(3, "蓝色");

	private int value;
	private String label;

	private Color(int value, String label) {
		this.value = value;
		this.label = label;
	}

	public int getValue() {
		return value;
	}

	public String getLabel() {
		return label;
	}
}

You can define abstract objects directly in the enumerationAt this time, each

Enumeration

Objects need to implement this abstract method, as shown in the following example

enum Color {

	RED {
		public String getLabel() {
			return "红颜色";
		}
	},
	GREEN {
		public String getLabel() {
			return "绿颜色";
		}
	};
	public abstract String getLabel();
}

public class Test {
	public static void main(String[] args) {
		for (Color color : Color.values()) {
			String label = color.getLabel();
			System.out.println(label);
		}
	}
}

•Enumeration noun

.

Enumeration Object: Get a specified enumeration object, as in the following example:

static T[] values()

: Get all enumeration objects in the custom enumeration, as in the following example

Enumeration types can be used in

•switch, as shown in the following example:

## The #•

Enum class is an abstract class, which is the parent class of the Java language enumeration type, that is, enum The keyword-defined enumeration type is equivalent to defining a inheritedjava.lang.Enumsubclass of the abstract classkind.

•

Enum Class construction method:

Ø

protected Enum(String name, int ordinal) : This constructor receives two parameters, one represents the name of the enumeration, and the other represents the serial number of the enumeration;

Related recommendations:

Detailed introduction to traversal of two enumeration types in JAVA

Introduction and use of enumerations

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