來自文件路徑的Java輸入和輸出流

Question

如何使用指定的文件路徑而不是資源文件夾中的文件作爲輸入或輸出流？這是我有的類，我想從特定的文件路徑中讀取，而不是將txt文件放在IntelliJ中的資源文件夾中。輸出流相同。任何幫助呈現將不勝感激謝謝。

輸入流

import java.io.*; 
import java.util.*; 

public class Example02 { 
    public static void main(String[] args) throws FileNotFoundException { 
     // STEP 1: obtain an input stream to the data 

     // obtain a reference to resource compiled into the project 
     InputStream is = Example02.class.getResourceAsStream("/file.txt"); 

     // convert to useful form 
     Scanner in = new Scanner(is); 

     // STEP 2: do something with the data stream 
     // read contents 
     while (in.hasNext()) { 
      String line = in.nextLine(); 
      System.out.println(line); 
     } 

     // STEP 3: be polite, close the stream when done! 
     // close file 
     in.close(); 
    } 
} 

輸出流

import java.io.*; 

public class Example03 
{ 
    public static void main(String []args) throws FileNotFoundException 
    { 
     // create/attach to file to write too 
     // using the relative filename will cause it to create the file in 
     // the PROJECT root 
     File outFile = new File("info.txt"); 

     // convert to a more useful writer 
     PrintWriter out = new PrintWriter(outFile); 

     //write data to file 
     for(int i=1; i<=10; i++) 
      out.println("" + i + " x 5 = " + i*5); 

     //close file - required! 
     out.close();    
    } 
} 

Answer 1

首選方法是java.nio.file.Files.newInputStream(Path)

try(final InputStream is = Files.newInputStream(Paths.get("/path/to/file")) { 
    //Do something with is 
} 

同爲OutputStream的Files.newOutputStream()

try(final OutputStream os = Files.newOutputStream(Paths.get("/path/to/file")) { 
    //Do something with os 
} 

通常，這裏是official tutorial from Oracle與IO一起工作。

Answer 2

，你可以使用一個文件對象：

File input = new File("C:\\[Path to file]\\file.txt"); 

Answer 3

首先，你必須確定你想要的路徑從中讀取文件琵琶路徑，像這樣：

String absolutePath = "C:/your-dir/yourfile.txt" 
InputStream is = new FileInputStream(absolutePath); 

它是寫文件，以及類似：用於獲取的InputStream

String absolutePath = "C:/your-dir/yourfile.txt" 
PrintWriter out = new PrintWriter(new FileOutputStream(absolutePath));