Java Class

Static

static method

static method指的是Class的方法，而不是instance的方法

public  class Patterns {

    public static Map<String, String> patternsMap;
    static {
        patternsMap = new HashMap<>();
        patternsMap.put("OTHER", ".");
		....
    }
    static String find(String key) {
        return patternsMap.get(key);
    }
}

static class

static class can only be defined in a inner Class, e.g.

public class OuterClass {
	public static class InnerClass{
		InnerClass(){
			System.out.println("============= static 内部类  InnerClass =============");
		}
	}
}
public class TestStaticClass {
	public static void main(String[] args) {
		// 不需要new一个OutClass
		new OuterClass.InnerClass();
	}
}