Programmer Think

To view the previous blogs, click [category column] at the top   What is a thread pool? Thread pool in Java is the concurrency framework with the most application scenarios. Almost all programs that need to execute tasks asynchronously or concurrently can use thread pool. In the development process, the rational use of thread pool can brin ...

Java memory structure 1. Program Counter Register Function: remember the execution address of the next jvm instruction For example, when executing instruction 0, the program counter will remember 3. When the execution of 0 is completed, the interpreter will take the instruction of 3 from the program counter, and so on. The instruction is i ...

Environment: Java 8 Cglib agent usage System.setProperty(DebuggingClassWriter.DEBUG_LOCATION_PROPERTY, "E://cglib"); Enhancer enhancer = new Enhancer() ; enhancer.setSuperclass(PersonDAOImpl.class) ; enhancer.setCallback(new MethodInterceptor() { @Override public Object intercept(Object obj, Method method, Object[] args, MethodProxy pr ...

Use of enumeration classes Define a simple enumeration class, which contains several enumeration constants. Examples are as follows: public enum Day { SUNDAY, MONDAY, TUESDAY, WEDNESDAY,THURSDAY, FRIDAY, SATURDAY } Java's switch statement parameters support the use of enumeration classes // Day is a variable of type day switch (day) { ...

The Java virtual machine loads the data describing the Class from the Class file into the memory, verifies, converts, parses and initializes the data, and finally forms a Java type that can be directly used by the virtual machine. This process is called the Class loading mechanism of the virtual machine. Class loading timing A type starts fro ...

preface: I don't know when it came out that using try catch in Java will seriously affect performance. However, is this really the case? Should we be afraid of try catch like tigers? 1, JVM exception handling logic Explicit exception throwing in Java programs is supported by the arrow instruction. In addition to actively throwing exception ...

Chapter 13 - StringTable 1. Basic characteristics of string String: string, represented by a pair of "" String s1 = "baidu"; //Definition of literal quantity String s2 = new String("hello"); String is declared as final and cannot be inherited String implements the Serializable interface: it means that the string supports ser ...

Initial class loading process When using a class, if the class file of the class is not loaded into memory, the system will initialize the class through the following three steps 1. Class loading → 2 Class connection (Link) → 3 Class initialization Class Load: read the class file of the class into memory and create a Java. Net file ...

Differences among String, StringBuilder and StringBuffer Know what it is and why. We want to answer the basic characteristics of String. String String is Java A class under Lang packageModified by the final keyword and cannot be inheritedThe internal data structure of JDK8 is char[] value modified by final, and JDK9 is Byte[] value array ...

Detailed explanation of virtual machine class loading mechanism 1 Overview The Java virtual machine loads the data describing the Class from the Class file into memory, verifies, converts, parses and initializes the data, and finally forms a Java type that can be directly used by the virtual machine. This process is called the Class loading m ...