Null pointer exception of getter setter in Java

I have one named shareddata Getter setter class of Java When I want to hint at it on my code, I get a null pointer exception This is the shareddata class:

public class SharedData {
private static SharedData instance = null;

public SharedData() {
    // randomizeServers();
}

// data to be shared
private double src_latitude = -1;
private double src_longitude = -1;
private double end_latitude = -1;
private double end_longitude = -1;

//Getter-Setters
public static SharedData getInstance() {
    return instance;
}
public static void setInstance(SharedData instance) {
    SharedData.instance = instance;
}

public double getSrc_latitude() {
    return src_latitude;
}
public void setSrc_latitude(double src_latitude) {
    this.src_latitude = src_latitude;
}
public double getSrc_longitude() {
    return src_longitude;
}
public void setSrc_longitude(double src_longitude) {
    this.src_longitude = src_longitude;
}
public double getEnd_latitude() {
    return end_latitude;
}
public void setEnd_latitude(double end_latitude) {
    this.end_latitude = end_latitude;
}
public double getEnd_longitude() {
    return end_longitude;
}
public void setEnd_longitude(double end_longitude) {
    this.end_longitude = end_longitude;
}

}@H_502_12@ 
 
这是我的代码：
 
 
 
 
SharedData sharedData ;  
       sharedData = SharedData.getInstance();
       sharedData.setSrc_latitude(latitude);
   sharedData.setEnd_longitude(longitude);@H_502_12@ 
 
有人可以帮帮我吗？谢谢 .

Solution
You never initialize shareddata, so its value is null. Calling a method on it will crash your program
I think you tried to use singleton pattern Try the following
Try this
private static SharedData instance = new SharedData();   \\ Initialize here

private SharedData() {        // Make it private....
    // randomizeServers();
}

// data to be shared
private double src_latitude = -1;
private double src_longitude = -1;
private double end_latitude = -1;
private double end_longitude = -1;

//Getter-Setters
public static SharedData getInstance() {
    return instance;
}@H_502_12@