BufferedWriter writer = null;
try {
    writer = new BufferedWriter(new FileWriter(fileName));
    writer.write(str);  // do something with the file we've opened
} catch (IOException e) {
   // handle the exception
} finally {
    try {
        if (writer != null)
            writer.close();
    } catch (IOException e) {
       // handle the exception
    }
}

try-with-resources：

try(BufferedWriter writer = new BufferedWriter(new FileWriter(fileName))){
    writer.write(str); // do something with the file we've opened
}
catch(IOException e){
    // handle the exception
}

Java理解此代碼的方式：

try語句之后在括號中打開的資源僅在此處和現(xiàn)在需要。.close()在try塊中完成工作后，將立即調(diào)用它們的方法。如果在try塊中拋出異常，無論如何我會關閉這些資源。

注意：

從Java 9開始，沒有必要在try-with-resources語句中聲明資源。

可以這樣做：

BufferedWriter writer = new BufferedWriter(new FileWriter(fileName));
try (writer) {
    writer.write(str); // do something with the file we've opened
}
catch(IOException e) {
    // handle the exception
}

到此這篇關于關于Java中的try-with-resources語句的文章就介紹到這了,更多相關Java try-with-resources語句內(nèi)容請搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關文章希望大家以后多多支持腳本之家！

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