文件類boolean canExecute() (File Class boolean canExecute())

• This method is available in package java.io.File.canExecute().

  軟件包java.io.File.canExecute()中提供了此方法。

• This method is used to execute the file and the file is represented by the abstract file path or in other words this method is used to test whether the application can execute the file or not.

  此方法用于執行文件，并且文件由抽象文件路徑表示，或者換句話說，該方法用于測試應用程序是否可以執行文件。

• The return type of this method is Boolean i.e. it returns true or false if true that means file can be executed by the application which is represented by the file path or in other words file already exists to execute and returns false that means file does not exist it means the application is not allowed to execute the file.

  此方法的返回類型為布爾值，即返回true或false，如果為true則表示文件可以由文件路徑表示的應用程序執行，或者換句話說，文件已經存在要執行，并且返回false表示文件不存在這意味著不允許應用程序執行文件。

• This method may raise an exception( i.e. Security Exception) if the execute access is not given to the file.

  如果未授予文件執行訪問權限，則此方法可能引發異常(即Security Exception)。

Syntax:

句法：

    boolean canExecute(){
}

Parameter(s):

參數：

We don't pass any object as a parameter in the method of the File.

我們不會在File方法中將任何對象作為參數傳遞。

Return value:

返回值：

The return type of this method is Boolean i.e. it returns true if the file already exists and allowed to execute the file which is denoted by the abstract file path returns false otherwise.

此方法的返回類型為Boolean，即如果文件已經存在并且允許執行該文件(由抽象文件路徑表示)，則返回true，否則返回false。

Java程序演示canExecute()方法的示例 (Java program to demonstrate example of canExecute() method)

// import the File class because we will use File class methods
import java.io.File;
//import the Exception class because it may raise 
// an exception when working with files
import java.lang.Exception;
public class ExecuteFile {
public static void main(String[] args) {
try {
// Specify the path of file and we use double slashes 
// to escape '\' character sequence for windows otherwise 
// it will be considerable as url.
File file1 = new File("C:\\Users\\computer clinic\\OneDrive\\Articles\\myjava.txt");
File file2 = new File("C:\\Users\\computer clinic\\OneDrive\\Articles\\java.txt");
// By using canExecute() is allowed to execute 
// the file if file is already exists and 
// it returns true if file is executable else false returns.
if (file1.canExecute())
System.out.println("This file " + file1.getName() + " " + "is executable");
else
System.out.println("This file " + file1.getName() + " " + "is not executable");
// By using canExecute() is not allowed to execute 
// the file because this file is not already exists 
// and it returns false.
if (file2.canExecute())
System.out.println("This file " + file2.getName() + " " + "is executable");
else
System.out.println("This file " + file2.getName() + " " + "is not executable");
} catch (Exception e) {
System.out.println("An error occurred.");
e.printStackTrace();
}
}
}

Output

輸出量

D:\Programs>javac ExecuteFile.java
D:\Programs>java ExecuteFile
This file C:\Users\computer clinic\OneDrive\Articles\myjava.txt is not executable
This file C:\Users\computer clinic\OneDrive\Articles\java.txt is not executable

翻譯自: https://www.includehelp.com/java/file-class-boolean-canexecute-method-with-example.aspx