ClassLoader類的getPackage()方法 (ClassLoader Class getPackage() method)

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

  getPackage()方法在java.lang包中可用。

• getPackage() method is used to return the package that has been defined in ClassLoader or the Package has been defined in ClassLoader ancestors.

  getPackage()方法用于返回在ClassLoader中定義的包或在ClassLoader祖先中定義的包。

• getPackage() 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.

  getPackage()方法是一個非靜態方法，只能通過類對象訪問，如果嘗試使用類名稱訪問該方法，則會收到錯誤消息。

• getPackage() method does not throw an exception at the time of returning an object of Package type.

  返回Package類型的對象時， getPackage()方法不會引發異常。

Syntax:

句法：

    protected Package getPackage(String pack_name);

Parameter(s):

參數：

• String pack_name – represents the name of the Package.

  字符串pack_name –表示軟件包的名稱。

Return value:

返回值：

The return type of this method is Package, it returns the following values based on the given cases,

此方法的返回類型為Package ，它根據給定的情況返回以下值：

• It returns the Package of the class which is loaded by the class loader of this Class.

  它返回由該類的類加載器加載的類的Package。

• It returns null, when no package is loaded by the class loader of this Class.

  當此Class的類加載器未加載任何包時，它返回null。

Example:

例：

// Java program to demonstrate the example 
// of Package getPackage(String pack_name) method of 
// ClassLoader
public class GetPackageOfClass extends ClassLoader {
void getPackage() throws ClassNotFoundException {
// It return the package
Package pack = super.getPackage("java.lang");
// Display Package Name
System.out.print("Package Name: ");
System.out.println(pack);
}
public static void main(String[] args) throws Exception {
GetPackageOfClass cp = new GetPackageOfClass();
cp.getPackage();
}
}

Output

輸出量

Package Name: package java.lang

翻譯自: https://www.includehelp.com/java/classloader-getpackage-method-with-example.aspx