来自文件路径的Java输入和输出流

Question

如何使用指定的文件路径而不是资源文件夹中的文件作为输入或输出流？这是我有的类，我想从特定的文件路径中读取，而不是将txt文件放在IntelliJ中的资源文件夹中。输出流相同。任何帮助呈现将不胜感激谢谢。

输入流

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(); 
    } 
} 

输出流

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

首选方法是java.nio.file.Files.newInputStream(Path)

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

同为OutputStream的Files.newOutputStream()

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

通常，这里是official tutorial from Oracle与IO一起工作。

Answer 2

，你可以使用一个文件对象：

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

Answer 3

首先，你必须确定你想要的路径从中读取文件琵琶路径，像这样：

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

它是写文件，以及类似：用于获取的InputStream

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