Java 7: Reading Notes on core technologies and best practices-java source code and byte code operations, java 7 Best Practices

Java 7: Reading Notes on core technologies and best practices-java source code and byte code operations, java 7 Best Practices

General process: developers write the java source code (. java)-> javac (compiler)-> java byte code (. class)-> java Virtual Machine (jvm) to run.

I. byte code format

1. byte code representation of common java source code

• Package name: com. java. sample-> com/java/sample
• Basic types: byte, char, double, float, int, long, boolean-> B, C, D, F, I, J, S, Z
• Reference Type: uniform use of "L" prefix and ";" suffix, such as: java. lang. String-> Ljava/lang/String;
• Array type: prefix "[", for example, double []-> [D
• Empty type: void-> V
• Method: int calculate (String str)-> type descriptor of the method: (Ljava/lang/String;) I. The signature information of the method must also be included.

2. Basic Format