java jar包示例

包类的getSpecificationVersion()方法 (Package Class getSpecificationVersion() method)

• getSpecificationVersion() method is available in java.lang package.

  getSpecificationVersion()方法在java.lang包中可用。

• getSpecificationVersion() method is used to retrieve the specification version of the package that this package implements and the version is a sequence of no negative decimal integer and is separated by "." and may have leading zeros.

  getSpecificationVersion()方法用于检索此程序包实现的程序包的规范版本，该版本是无负十进制整数的序列，并用“。”分隔。 并可能有前导零。

• getSpecificationVersion() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  getSpecificationVersion()方法是一种非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。

• getSpecificationVersion() method does not throw an exception at the time of returning the specification version of the package.

  返回包的规范版本时， getSpecificationVersion()方法不会引发异常。

Syntax:

句法：

    public String getSpecificationVersion();

Parameter(s):

参数：

• It does not accept any parameter.

  它不接受任何参数。

Return value:

返回值：

The return type of this method is String, it returns the version of the specification that this package implements otherwise it returns null when specification version of the package is not known.

此方法的返回类型为String ，它返回此程序包实现的规范的版本，否则，当未知程序包的规范版本时，它返回null。

Example:

例：

// Java program to demonstrate the example 
// of String getSpecificationVersion()
// of Package method
public class GetSpecificationVersion {
public static void main(String[] args) {
// Get Package by using getPackage() method
Package pkg = Package.getPackage("java.util");
// Get specification version of the package by using 
// getSpecificationVersion() and stored in a variable
// called sversion
String sversion = pkg.getSpecificationVersion();
// Display version of the package
System.out.print("Package Version: ");
System.out.print(sversion);
}
}

Output

输出量

Package Version: 1.4

翻译自: https://www.includehelp.com/java/package-getspecificationversion-method-with-example.aspx

java jar包示例