java write string to file code example

Example 1: writing to a file in java

import java.io.FileWriter;   // Import the FileWriter class
import java.io.IOException;  // Import the IOException class to handle errors

public class WriteToFile {
  public static void main(String[] args) {
    try {
      FileWriter myWriter = new FileWriter("filename.txt");
      myWriter.write("Files in Java might be tricky, but it is fun enough!");
      myWriter.close();
      System.out.println("Successfully wrote to the file.");
    } catch (IOException e) {
      System.out.println("An error occurred.");
      e.printStackTrace();
    }
  }
}

Example 2: write file java

@Test
public void givenUsingJava7_whenWritingToFile_thenCorrect() 
  throws IOException {
    String str = "Hello";
 
    Path path = Paths.get(fileName);
    byte[] strToBytes = str.getBytes();
 
    Files.write(path, strToBytes);
 
    String read = Files.readAllLines(path).get(0);
    assertEquals(str, read);
}

Example 3: java stream write to file

@Test
public void givenWritingStringToFile_whenUsingPrintWriter_thenCorrect() 
  throws IOException {
    FileWriter fileWriter = new FileWriter(fileName);
    PrintWriter printWriter = new PrintWriter(fileWriter);
    printWriter.print("Some String");
    printWriter.printf("Product name is %s and its price is %d $", "iPhone", 1000);
    printWriter.close();
}

Example 4: java write to file

PrintWriter writer = new PrintWriter("the-file-name.txt", "UTF-8");
writer.println("The first line");
writer.println("The second line");
writer.close();