Error on my Processing GUI code for Arduino , I need some help

Processing Electronics (Arduino, etc.)
38

now I used trim() to separate the actual value from parameter but also I got another error -line 65 NullPointerException . Any suggestions ?

import processing.serial.*;


String winddir;
String windspeedmph;
String windgustmph;
String windgustdir;
String windspdmph_avg2m;
String winddir_avg2m;
String windgustmph_10m;
String windgustdir_10m;
String humidity;
String tempf;
String rainin;
String dailyrainin;
String pressure;
String batt_lvl;
String light_lvl;

 String a1 = trim(winddir);
 String a2 = trim(windspeedmph);
 String a3 = trim(windgustmph);
 String a4 = trim(windgustdir);
 String a5 = trim(windspdmph_avg2m);
 String a6 = trim(winddir_avg2m);
 String a7 = trim(windgustmph_10m);
 String a8 = trim(windgustdir_10m);
 String a9 = trim(humidity);
 String a10 = trim(tempf);
 String a11 = trim(rainin);
 String a12 = trim(dailyrainin);
 String a13 = trim(pressure);
 String a14 = trim(batt_lvl);

String myString = null;
Serial myPort;

void setup()
{
size(700,700);
String portName = Serial.list()[5]; 
myPort = new Serial(this, portName, 9600);
myPort.clear();
myString = myPort.readStringUntil('!');
myString = null;
}
void draw()
{
  while ( myPort.available() > 0) 
  {  
  myString = myPort.readStringUntil('!'); 
  if (myString != null) {
    println(myString);
    
    String myString = myPort.readString();
    
      
        
     

      
background(0);
textSize(20);
text("Wind direction:",50,50);
text(a1,250,50);
text("Wind speed:" ,50,100);
text(a2,250,100);
text("Wind gust:",50,150);
text(a3,250,150);
text("Wind gust direction:",50,200);
text(a4,250,200);
text("Humidity:",50,250);
text(a5,250,250);
text("Temperature",50,300);
text(a6,250,300);
text("Rainfall:",50,350);
text(a7,250,350);
text("Daily rain:",50,400);
text(a8,250,400);
text("Pressure",50,450);
text(a9,250,450);
text("Battery level:",50,500);
text(a10,250,500);
text("Light level:",50,550);
text(a11,250,550);

     
   }
  } 
}