If you teach yourself, you won't get the first two, only the third one is possible, but your resume may be eliminated under the screening of the first two conditions, and there is no chance to show your strength at all, unless some companies don't pay attention to your resume and only pay attention to the comprehensive results such as interview and written test.
Extended data:
Matters needing attention in writing java programs:
Case-sensitive: Java is case-sensitive, which means that the identifiers Hello and hello are different.
Class name: For all classes, the first letter of the class name should be capitalized. If the class name consists of several words, the first letter of each word should be capitalized, for example, MyFirstJavaClass.
Method name: All method names should start with lowercase letters. If the method name contains several words, the first letter of each word should be capitalized, for example, myFirstJavaClass.