Buttons, Reading Files, and reading pastbin files.

Newbie & Debugging Questions
#1

Hi,
I would like to know how to create buttons for my main menu, read/write files(for save data), and read online data for pruchase-able data later on. Sorry if this is nooby as i dont even know where to start.

Thanks,
Drok

#2

What are you using? Swing? LibGDX? Something else?

What have you tried? What has google told you? Which exact part of this are you stuck on?

Can you create a separate example program that just prints something to the console when you click a button?
Can you create a separate example program that just writes to a file?
Can you create a separate example program that just reads from a file?
Can you create a separate example program that just reads from online data (do you mean a URL or a database or something else)?

The point of those questions is to encourage you to break this down into smaller pieces. Focus on one step at a time, and post an MCVE when you get stuck.

Good luck!

#3

Ok i got it to work but it doesnt work how i expected. I need it to read specific lines(such as line 2, 6, 10) and take the int/string value from that and apply it somewhere else(i think i said that right). Here is what i curently have:

package alfitaria.entity.player;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;

public class LoadPlayerFiles {
  
  public static void Load() throws IOException{
	  LoadPlayerFiles text = new LoadPlayerFiles();
    
    //treat as a small file
    List<String> lines = text.readSmallTextFile(FILE_NAME);
    log(lines);
    lines.add("This is a line added in CODE.");
    text.writeSmallTextFile(lines, FILE_NAME);
    
    //treat as a large file - use some buffering
    text.readLargerTextFile(FILE_NAME);
    lines = Arrays.asList("Down to the Waterline", "Water of Love");
    text.writeLargerTextFile(OUTPUT_FILE_NAME, lines);   
  }

  final static String FILE_NAME = "C:\\Temp\\input.txt";
  final static String OUTPUT_FILE_NAME = "C:\\Temp\\output.txt";
  final static Charset ENCODING = StandardCharsets.UTF_8;
  
  //For SMALLER files

  /**
   Note: the javadoc of Files.readAllLines says it's intended for small
   files. But its implementation uses buffering, so it's likely good 
   even for fairly large files.
  */  
  List<String> readSmallTextFile(String aFileName) throws IOException {
    Path path = Paths.get(aFileName);
    return Files.readAllLines(path, ENCODING);
  }
  
  void writeSmallTextFile(List<String> aLines, String aFileName) throws IOException {
    Path path = Paths.get(aFileName);
    Files.write(path, aLines, ENCODING);
  }

  //For larger files
  
  void readLargerTextFile(String aFileName) throws IOException {
    Path path = Paths.get(aFileName);
    try (Scanner scanner =  new Scanner(path, ENCODING.name())){
      while (scanner.hasNextLine()){
        //PROCESS each line in some way
        log(scanner.nextLine());
      }      
    }
  }
  
  void readLargerTextFileAlternate(String aFileName) throws IOException {
    Path path = Paths.get(aFileName);
    try (BufferedReader reader = Files.newBufferedReader(path, ENCODING)){
      String line = null;
      while ((line = reader.readLine()) != null) {
        //process each line in some way
        log(line);
      }      
    }
  }
  
  void writeLargerTextFile(String aFileName, List<String> aLines) throws IOException {
    Path path = Paths.get(aFileName);
    try (BufferedWriter writer = Files.newBufferedWriter(path, ENCODING)){
      for(String line : aLines){
        writer.write(line);
        writer.newLine();
      }
    }
  }

  private static void log(Object aMsg){
    System.out.println(String.valueOf(aMsg));
  }
  
}

P.S. this will be used to load worlds and player files(such as inventory, id, health, maxhealth ect) if it helps.

#4

Then you need to just keep track of the line number you’re on, and either parse the line or don’t depending on the current line number.

You can also take a look at the Integer class for useful methods for parsing a String value.

#5

Also the Scanner class you are already using has support for reading numbers via the nextInt(), nextFloat() (or something similar to these) etc. methods.

#6

Ok i got it to read the file that is located on the pc but what if i wanted to read a pastebin.com file for example from here: http://pastebin.com/dpQWKeHU. i need to do this for donations/personal/nonhackable data later on(i hope this is the right way to do it). Thanks. Also how do i add buttons to my main menu?