Comparison of null and "" in java

Comparison of null and "" in java

Directly upload code and screenshots

public static void main(String[] args) {
		String s = null;
		System.out.println(s != null);//false
		System.out.println(s != "");//true
		System.out.println("".equals(s));//false
		System.out.println(!"".equals(s));//true
		System.out.println(s != null || s != "");//true
		System.out.println("****************");
		
		String s2 = "";
		System.out.println(s2 != null);//true
		//
		System.out.println(s2 == "");//true
		//
		System.out.println(s2 != "");//false
		
		System.out.println("".equals(s2));//true
		System.out.println(s2.equals(""));//true
		System.out.println(!"".equals(s2));//false
		System.out.println(s2 != null || s2 != "");//true
		
		String s3 = "江西省赣州市于都县";
		//
		System.out.println(s2 == s3);//false
		//
		System.out.println(s2 != s3);//true
	}

The results of the operation are as follows: