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Solved the problem by implementing the below object and using apache commons MultiValuedMap.

By design, you can't sort a HashMap. If you need to keep a specific order in your map, it is recommended to use a Map implementation like TreeMap.

What you can do if you want to iterate over a HashMap in a specific order, is getting the keys and sort them. Then you can iterate over the keys and lookup your values accordingly:

Instead of calling the script with

In Modbus-TCP:

• transaction is 2Byte == Short == H
• identifier is 2Byte == Short == H
• length is 2Byte == Short == H
• unitid is 1Byte == B
• fcode is 1Byte == B
• reg_addr is 2Byte == Short == H
• count is 2Byte == Short == H

Thus, the format in your case will be >HHHBB or >3H2B:

You can use GeoFire , a firebase library that uses GeoHashes to merge lat+lon into a single property.That way you can do the distance filtering directly on the database.

You should have 2 entries in firebase database,one for setting your object location and one for setting your object with its fields.

As you can see they have the same id.So first you are queriing for nearby object by GeoFire in geo_data entry,and you will get the ids of the object which are nearby,then you can retreive object with its properties directly from database using the ids in my case in user_data entry