可以使用Java的文件類方法exists()，它可以測(cè)試給定的路徑名表示的文件或目錄是否存在。如果存在的話返回“true”，否則就是返回“false”。? ? ? ? （推薦學(xué)習(xí)：java課程）
Java文件類以抽象的方式代表文件名和目錄路徑名。該類主要用于文件和目錄的創(chuàng)建、文件的查找和文件的刪除等。
public boolean exists()
測(cè)試此抽象路徑名表示的文件或目錄是否存在。
實(shí)例：
String filePth= "D:\\bh\\key\\rsa_public_key.pem";
File file = new File(filePth);
if(!file.exists()){
// 文件不存在
throw new RuntimeException("文件不存在，請(qǐng)聯(lián)系管理員");
}The above is the detailed content of How to determine whether a file exists in java. For more information, please follow other related articles on the PHP Chinese website!
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