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Java connector to QikkDB database

QikkDBClient.java: class containing functions necessary to establish connection and get the data

ExampleApp.java: sample usage of QikkDBClient

Usage

Creating connection

QikkDBClient client = new QikkDBClient("192.168.1.230", 12345);
try {
	client.Connect();
} catch (IOException e) {
	System.out.println("Error connecting to server " + e.toString());            
}

Switching database

try {
	client.UseDatabase("default_db");            
} catch (IOException | QueryException e) {
	System.out.println("Error changing database " + e.toString());
}

Querying

Query is executed using Query() method. Getting result is done by calling GetNextQueryResult() method which returns bulk of rows (1000 rows). All rows could be retrieved by iterating until (null, null) pair is returned by GetNextQueryResult().

Executing query and priting the result
try {
	client.Query("SELECT * FROM T_default1 LIMIT 10;");
    Pair<ColumnarDataTable, Dictionary<String, Float>> result = client.GetNextQueryResult();
    ColumnarDataTable resultData = result.getFirst();
} catch (IOException | QueryException e) {
	System.out.println("Error while execting query " + e.toString());
}

Bulk import

ColumnarDataTable dataTable = new ColumnarDataTable("jimport");        
dataTable.AddColumn("col_bool", Boolean.class);
dataTable.AddColumn("col_int", Integer.class);
dataTable.AddColumn("col_long", Long.class);
dataTable.AddColumn("col_float", Float.class);
dataTable.AddColumn("col_double", Double.class);
dataTable.AddColumn("col_string", String.class);
dataTable.AddColumn("col_point", QPoint.class);
dataTable.AddColumn("col_polygon", QComplexPolygon.class);
dataTable.AddRow(new Object[] { true, 1, 11l, 1.1f, 11.1, "hello1", new QPoint(10.4f, 11.5f), new QComplexPolygon("POLYGON((2 2, 4 2, 4 4, 2 2),(5 15.5, 10.5 10.5, 20.5 10.5, 25 15.5, 20.5 20, 10.5 20, 5 15.5))")  });

try {
    client.BulkImport(dataTable);
} catch (QueryException e) {            
    System.out.println("Error while executing bulk import " + e.toString());
}

Disconnecting

try {
    client.Close();
} catch (IOException e) {
    System.out.println("Error disconnecting from the server " + e.toString());            
}

Generating Protobuf classes

Generating classes are from proto/ folder with command

protoc --proto_path=. --java_out=../src/main/java/ Message/InfoMessage.proto Message/QueryMessage.proto Message/QueryResponseMessage.proto Message/SetDatabaseMessage.proto Message/BulkImportMessage.proto Message/CSVImportMessage.proto Types/ComplexPolygon.proto Types/Point.proto