Analysis of the "SHIMS" framework technology in the Java class library
Analysis of the "SHIMS" framework technology in the Java class library
preface:
As an object -oriented programming language, Java has a wide and rich class library, providing developers with many powerful tools and libraries.Among them, the "SHIMS" framework technology in the Java class library is an important development tool. It is widely used in the Java class library to provide compatibility support for different versions or different platforms.This article will analyze the "SHIMS" framework technology in the Java library, including the introduction of its concepts, principles, and example code.
1. Concept:
During the development of Java, due to the differences between different versions or the differences between different platforms, the same class or method cannot be used directly in some cases.To solve this problem, the "SHIMS" framework technology was introduced in the Java library.In short, the "SHIMS" framework technology can convert different versions or different platforms into compatible code by providing an intermediate layer in the Java class library.
2. Principles:
The "SHIMS" framework technology in the Java library is implemented based on the adapter mode.The adapter mode is a structural design mode, which is the purpose of converting a class interface into another interface that meets the expectations of the client.In the "SHIMS" framework technology, the original class or methods is packaged and transformed by using the adapter mode to achieve compatibility support for different versions or different platforms.
Third, sample code:
Below is a simple example to demonstrate the use of "Shims" framework technology.Suppose we have a class called "StringUtils", which contains a method "ReverseSestring" to reverse the string.Our goal is to achieve compatibility support for different versions of Java.
First of all, we need to define an interface "StringReverser" to unify the reversal string method of different versions:
public interface StringReverser {
String reverseString(String str);
}
Then, we create a adapter "StringUtilSadapter" to implement the "StringReverser" interface and call the corresponding version of the reversal string method:
public class StringUtilsAdapter implements StringReverser {
Private StringUtils Stringutils; // The original StringUtils class
public StringUtilsAdapter() {
if (isJava8OrEarlier()) {
StringUtils = New StringUtilsjava8 (); // Java 8 and the StringUtils class used in previous versions
} else {
StringUtils = New StringUtilsjava11 (); // java 11 and subsequent version of the StringUtils class
}
}
@Override
public String reverseString(String str) {
return stringUtils.reverseString(str);
}
private boolean isJava8OrEarlier() {
// Judging whether the current Java version is 8 and previous versions
// Implementation is omitted, you can use the Getproperty method of the Java System class to obtain the Java version number for comparison
}
}
Finally, we can use "StringUtilSadapter" in the application to achieve compatibility support for different versions of Java:
public class Application {
public static void main(String[] args) {
String input = "Hello World!";
StringReverser reverser = new StringUtilsAdapter();
String reversed = reverser.reverseString(input);
System.out.println(reversed);
}
}
In the above examples, by using the "StringUtilSadapter" adapter class, we can achieve compatibility support for different versions of Java without changing the application logic.In this way, whether it is running the program on the Java 8 and the previous versions or on the version of the Java 11 and the subsequent version, the correct result can be obtained.
in conclusion:
The "SHIMS" framework technology in the Java class library provides compatibility support for different versions or different platforms by using the adapter mode.It can solve some programming problems caused by differences, so that developers can more conveniently write codes of cross -version or cross -platform code.Through the shallow analysis of this article, it is believed that readers have a deeper understanding of the "SHIMS" framework technology in the Java class library and can be flexibly applied.
