1.1 Java Overview+ 1.2 Java Motion Mechanism + 1.3 IntelliJ IDEA Development Tools+ 2.1 Object-oriented Thinking + 2.2 Class Definition+ 2.3 Creation and Use of Object + 2.4 Access Control Permission + 2.5 Encapsulation + 2.6 Construction Method + 2.7 Inheritance + 2.8 Method Rewriting+ 2.9 Polymorphism + 3.1 Abnormal Overview + 3.2 Abnormal Classification + 3.3 Abnormal Handling + 3.4 Abnormal Handling Keyword + 4.1 String Class + 4.2 Random Class + 4.3 Calendar Class+ 4.4 DateFormat Class + 4.5 Wrapper Class + 5.1 Collections Overview + 5.2 List Interface + 5.3 Collections Iterate + 5.4 Set Interface + 5.5 Map Interface + 5.6 Collections Tool Class + 5.7 Arrays Tool Class +