如何计算从txt文件中获得的值？

Question

所以我试图读取我从results.txt文件中获取的值并根据CGPA格式计算它们，但似乎我尝试的方法不起作用。我想知道是否有人可以帮助我，这是我的客户服务器任务。计算部分位于View（）方法下。 PS抱歉，如果我的代码太难阅读，我仍然不习惯使用java，这是我第一次在这里发帖

import java.net.*; 
import java.io.*;
import java.lang.*;
public class MultiClientHandler1 extends Thread {
  private Socket client;
  private BufferedReader in, in2,in3;
  private PrintWriter out, out2;
  private String received, data,result;
  private String array[], array2[], array3[],array4[];
  private int found=0;

  public MultiClientHandler1(Socket socket) {
    client = socket;
    try {
      in = new BufferedReader(new InputStreamReader(client.getInputStream()));
      out = new PrintWriter(client.getOutputStream(), true);
      out2 = new PrintWriter(new FileWriter("students.txt", true));
    } catch(IOException e) {
      e.printStackTrace();
    }
  }

  public void Register() {
    String reply="";
    array = received.split(":");

    if(array[1].length() != 7)
      reply = "Err1";
    else if(array[2].length() < 5)
      reply = "Err2";
    else if(array[3].length() < 5)
      reply = "Err3";
    else {
      reply= "+OK";
      out2.println(array[1]+":"+array[2]+":"+array[3]);
      out2.close();
    }
    out.println(reply);
  }

  public void login() throws IOException {
    in2 = new  BufferedReader(new FileReader("students.txt"));
    while((data = in2.readLine()) != null) {
      array3=data.split(":");
      if((array2[1].equals(array3[0])) && (array2[2].equals(array3[1]))) {
        out.println("Login successfully");
        found=1;
        break;
      }
    }
    if(found==0)
      out.println("Login Error");
  }

  public void View() throws IOException {
    String grade = "", cgpa = "";
    int IntValue = 0, IntCH = 0, IntCGPA = 0, IntArray = 0;
    in3 = new BufferedReader(new FileReader("results.txt"));
    while((result = in3.readLine()) != null) {
      array4=result.split(":");
      if((array2[1].equals(array4[0])) && (array2[2].equals(array4[1]))) {
        grade += array4[2] + " " + array4[3] + " " + array4[4] + "...........";
        found = 1;
        if(array4[3] == "A") {
          IntArray = Integer.parseInt(array4[3]);
          IntValue = IntArray * 4;
        } else if(array4[3] == "B") {
          IntArray = Integer.parseInt(array4[3]);
          IntValue = IntArray * 3;
        }
        IntCH += IntArray;
        IntCGPA = IntValue/IntCH;
        out.println(IntCGPA);
      }
      if(found==0)
        out.println("No Records");
    }
    out.println(grade);
  }

  public void run() {
    try {
      do {
        found=0;
        received = in.readLine();
        array2=received.split(":");
        if (received.equals("QUIT")) break;

        switch(received.charAt(0)) {
          case 'R':
            Register();
            break;
          case 'L':
            login();
            break;
          case 'V':
            View();
            break;
        }
      } while (!received.equals("QUIT"));
    } catch(IOException e) {
      e.printStackTrace();
    } finally {
      try {
        if(client != null) {
          System.out.println("Closing down connection...");
          client.close();
        }
      } catch(IOException e) {
        e.printStackTrace();
      }
    }
  }
}
    these are the content in the results.txt file
    0118210:1801:XDCS1094:A:4
    0118210:1801:XDCS2034:B+:4
    0118210:1801:XDCS1043:C:3
    0118024:1801:XDCS1094:B:4
    0118024:1801:XDCS2094:A:4