[Util] Saving and Loading locations to and from Strings

Hey everybody, if you are anything like me at all, you hate having to hard code in location data for a plugins that need to save a location even after the server restarts. I have written a few basic methods that will solve these problems, and convert Locations to Strings, and convert those Strings back into location objects.

Serialize Location (Convert to String)

Code:java

public static String serializeLocation(Location l) {
String s = "";
s += "@w;" + l.getWorld().getName();
s += ":@x;" + l.getBlockX();
s += ":@y;" + l.getBlockY();
s += ":@z;" + l.getBlockZ();
s += ":@p;" + l.getPitch();
s += ":@ya;" + l.getYaw();
return s;
}

Deserialize Location (Convert back to Location object)

Code:java

public static Location deserializeLocation(String s) {
Location l = new Location(Bukkit.getWorlds().get(0), 0, 0, 0);
String[] att = s.split(":");
for(String attribute : att) {
String[] split = attribute.split(";");
if(split[0].equalsIgnoreCase("@w"))
l.setWorld(Bukkit.getWorld(split[1]));
if(split[0].equalsIgnoreCase("@x"))
l.setX(Double.parseDouble(split[1]));
if(split[0].equalsIgnoreCase("@y"))
l.setY(Double.parseDouble(split[1]));
if(split[0].equalsIgnoreCase("@z"))
l.setZ(Double.parseDouble(split[1]));
if(split[0].equalsIgnoreCase("@p"))
l.setPitch(Float.parseFloat(split[1]));
if(split[0].equalsIgnoreCase("@ya"))
l.setYaw(Float.parseFloat(split[1]));
 
}
return l;
}

There are many things you can do with just these few lines of code, such as saving a spawn location, or saving the location of a block, the possibilities are endless.

Let me know if there are any other code snippets you would like, and I'll see what I can do!
~Shadowwolf97

 

Thanks, a useful snippet!

 

Shadowwolf97
You could have gone by using array indexes instead of attributes, that would shorten the code a bit.

 

So many if loops and the attributes part is inefficient. No need to split twice.

 

Yeah I know, Ill revise the code, I had originally wanted to have it convert multiple locations to a String, but I decided against that, and just forgot to update the method.

I suppose I could have, I just like being able to read the string and understand what is going on.

 

Code:java

public String locToString(Location loc){
StringBuilder sb = new StringBuilder();
sb.append(loc.getWorld().getName());
sb.append(';');
sb.append(loc.getX());
sb.append(';');
sb.append(loc.getY());
sb.append(';');
sb.append(loc.getZ());
sb.append(';');
sb.append(loc.getPitch());
sb.append(';');
sb.append(loc.getYaw());
return sb.toString();
}

Code:java

public Location strToLoc(String str){
String[] data = str.split(';');
return new Location(Bukkit.getWorld(data[0]), data[1], data[2], data[3], data[4], data[5]);
}

Untested, but should be correct

 

Cirno
You forgot to return sb.toString() at the end

 

Shhhh... Only dreams now.

 

Thank you!

 

Thanks for that!
Just wanted to add a bit to the strToLoc method, as the Doubles and Floats were never parsed.

Code:java

 public Location strToLoc(String str){
        String[] data = str.split(";");
        return new Location(Bukkit.getWorld(data[0]), Double.parseDouble(data[1]), Double.parseDouble(data[2]), Double.parseDouble(data[3]), Float.parseFloat(data[4]), Float.parseFloat(data[5]));
    }

 

String based serialization is joke, what about byte[]?

Code:

	public static final byte[] intToByteArray(int value) {
	    return new byte[] {
	            (byte)(value >>> 24),
	            (byte)(value >>> 16),
	            (byte)(value >>> 8),
	            (byte)value};
	}
	
	
	public static byte[] Coordinate2ByteNONEG(int XZ)
	{
		if (XZ < 0)XZ *= -1;
		return new byte[]{(byte) (XZ >>> 8),(byte) XZ};
	}
	
	public static int Byte2CoordinateNONEG(byte[] bytes)
	{
		return ((bytes[0] & 0xFF) << 8) + (bytes[1] & 0xFF);
	}
	
	public static byte ApplyNegs(byte B,boolean X, boolean Z)
	{
		if (X)
			B += 64;
		if (Z)
			B *= -1;
		return B;
	}
	public static byte GetNeg(byte B,boolean isX)
	{
		if (isX ? (B & 64)==0 : B < 0)
			return -1;
		return 1;
	}
	
	public static byte GetValue(byte B)
	{
		if (B < 0) B *= -1;
		return (byte) (B & 63);
	}
	
    static float factor = 360f/255f;
	public static byte Compress360(float F)
	{
		return (byte) (F/factor);
	}
	public static float Extract360(byte B)
	{
		return (B & 0xFF)*factor;
	}
	
	
	public static byte[] serializeLocation(Location l) {

		byte[] data = new byte[8];

		data[0] = ApplyNegs((byte) Bukkit.getWorlds().indexOf(l.getWorld()),l.getBlockX() <0 , l.getBlockY() < 0);
		byte[] x = Coordinate2ByteNONEG(l.getBlockX());
		data[1] = x[0];
		data[2] = x[1];
		data[3] = (byte) l.getBlockY();
		byte[] y = Coordinate2ByteNONEG(l.getBlockY());
		data[4] = y[0];
		data[5] = y[1];
		data[6] = Compress360(l.getPitch());
		data[7] = Compress360(l.getYaw());

		return data;
	}

 

What are the advantages of using byte arrays instead of Strings?

 

how many bytes your string based serialization consume per location?

 

I highly doubt a sheer couple of bytes makes much of a difference. Performance wise, your method is probably better by a handful of nanoseconds, a couple of milliseconds at most. Remember; premature optimization is the source of all evil.

 

looks like you dont understand how JVM works, what about benchmarking before posting something like this? Cirno