Migrate Sybase T-SQL to Java

Conversion Samples of Sybase T-SQL to Java

Ispirer Toolkit analyzes all object dependencies during the conversion process and provides not only line-by-line conversion, but resolves type conversions as well. The software understands and transforms the necessary inheritance dependencies. It parses the entire source code, builds an internal tree with all the information about the objects, and uses it in the migration process.

We convert Sybase ASE stored procedures to Java with attention to all the specifics

• System functions (getdate(), isnull()). In Java, their equivalents are found in standard library classes or utility helpers.
• Control flow (if, while). During migration, they map naturally to Java’s if and while constructs without semantic loss.
• Arithmetic operations (sum, average, conditional discount). When migrating to Java, these operations are usually extracted into utilit methods that are null-safe. This means they handle null inputs gracefully, avoiding NullPointerExceptionand ensuring consistent. This approach also centralizes business rules and increases code reusability.
• Error handling via @@error and raiserror. In Java, these patterns are delegated to utility classes (e.g., ErrorUtil) for unified exception processing.
• Cursors to retrieve and iterate through records. In Java migration scenarios, cursors are supported via CursorReader and CursorStatusService, which provide similar functionality for row-by-row iteration and cursor state management.
• Output parameter to return the computed total amount. In Java, this mechanism is typically expressed through return Map structures, enabling multiple values to be returned in a type-safe manner.

The code samples below provide you with more details.

• Sybase T-SQL

   
  create procedure sp_demo_orders
      @CustomerId int,
      @TotalAmount numeric(12,2) output
  as
  begin
      declare @OrderId int
      declare @OrderAmount numeric(10,2)
      declare @CurrentDate datetime
      declare @Count int
      declare @SumAmount numeric(12,2)
   
      select @CurrentDate = getdate()
      select @TotalAmount = 0
      select @SumAmount = 0
      select @Count = 0
   
      print "Order processing started at " + convert(varchar(30), @CurrentDate)
   
      if @CustomerId is null or @CustomerId <= 0
      begin
          raiserror 50010 "Invalid Customer Id"
          return
      end
   
      -- Cursor for orders of this customer
      declare order_cursor cursor for
          select OrderId, Amount
          from Orders
          where CustomerId = @CustomerId
   
      open order_cursor
      fetch order_cursor into @OrderId, @OrderAmount
   
      while @@FETCH_STATUS = 0
      begin
          select @Count = @Count + 1
          select @SumAmount = @SumAmount + isnull(@OrderAmount, 0)
   
          -- Apply discount logic
          if @OrderAmount > 1000
          begin
              print "Large order " + convert(varchar, @OrderId) + 
                    ": applying discount"
              select @OrderAmount = @OrderAmount * 0.9
          end
   
          -- Simulate error on negative amount
          if @OrderAmount < 0
          begin
              raiserror 50011 "Negative order amount detected"
              close order_cursor
              deallocate cursor order_cursor
              return
          end
   
          select @TotalAmount = @TotalAmount + @OrderAmount
   
          fetch order_cursor into @OrderId, @OrderAmount
      end
   
      close order_cursor
      deallocate cursor order_cursor
   
      print "Customer " + convert(varchar, @CustomerId) + 
            " has " + convert(varchar, @Count) + " orders"
      print "Total before discounts: " + convert(varchar, @SumAmount)
      print "Final total amount: " + convert(varchar, @TotalAmount)
      print "Average order: " + 
            convert(varchar, @TotalAmount / nullif(@Count,0))
   
      print "Order processing finished at " + convert(varchar(30), getdate())
  end
   

  → Java

   
  import com.sql4j.db.cursor.*;
  import com.sql4j.exception.ErrorUtil;
  import com.sql4j.transaction.aop.TransactionStatus;
  import com.sql4j.util.*;
  import java.math.BigDecimal;
  import java.time.LocalDateTime;
  import java.util.*;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Service;
  import org.springframework.web.context.annotation.RequestScope;
  @Service
  @RequestScope
  public class SpDemoOrders implements ISpDemoOrders {
  	@Autowired
  	private ErrorUtil errorUtil;
  	@Autowired
  	private CursorStatusService cursorStatusService;
  	@TransactionStatus
  	@Override
  	public Map< String, Object > spSpDemoOrders(Integer customerid, BigDecimal totalamount) {
  		Map<String, Object> outData = new HashMap<>();
  		outData.put("retStatus", 0);
   
  		try {
  			Integer orderid = null;
  			BigDecimal orderamount = null;
  			LocalDateTime currentdate = null;
  			Integer count = null;
  			BigDecimal sumamount = null;
  			currentdate = TimeUtil.getDate();
  			totalamount = new BigDecimal("0");
  			sumamount = new BigDecimal("0");
  			count = 0;
  			System.out.println(StringUtil.concat("Order processing started at ", Converter.toString(currentdate)));
   
  			if (customerid == null || ComparisonUtil.isLessOrEqual(customerid, 0)) {
  				errorUtil.raisError(50010, "Invalid Customer Id");
  				return outData;
  			}
   
  			CursorReader orderCursor = new CursorReader(cursorStatusService, true, "select OrderId, Amount " +
  			        "from Orders " +
  			        "where CustomerId = :CUSTOMERID ", "CUSTOMERID", customerid);
  			orderCursor.open();
   
  			if (orderCursor.fetchNext()) {
  				orderid = orderCursor.getColumnValue(Integer.class);
  				orderamount = orderCursor.getColumnValue(BigDecimal.class);
  			}
   
  			while (ComparisonUtil.areEqual(cursorStatusService.getFetchStatus(), 0)) {
  				count = Converter.toInteger(MathUtil.add(count, 1));
  				sumamount = MathUtil.add(sumamount, ComparisonUtil.isNull(orderamount, new BigDecimal("0")));
   
  				// Apply discount logic
  				if (ComparisonUtil.isGreaterThan(orderamount, 1000)) {
  					System.out.println(StringUtil.concat("Large order ", Converter.toString(orderid), ": applying discount"));
  					orderamount = MathUtil.multiply(orderamount, new BigDecimal("0.9"));
  				}
   
  				// Simulate error on negative amount
  				if (ComparisonUtil.isLessThan(orderamount, 0)) {
  					errorUtil.raisError(50011, "Negative order amount detected");
  					orderCursor.close();
  					orderCursor.deallocate();
  					return outData;
  				}
   
  				totalamount = MathUtil.add(totalamount, orderamount);
   
  				if (orderCursor.fetchNext()) {
  					orderid = orderCursor.getColumnValue(Integer.class);
  					orderamount = orderCursor.getColumnValue(BigDecimal.class);
  				}
  			}
   
  			orderCursor.close();
  			orderCursor.deallocate();
  			System.out.println(StringUtil.concat("Customer ", Converter.toString(customerid), " has ", Converter.toString(count), " orders"));
  			System.out.println(StringUtil.concat("Total before discounts: ", Converter.toString(sumamount)));
  			System.out.println(StringUtil.concat("Final total amount: ", Converter.toString(totalamount)));
  			System.out.println(StringUtil.concat("Average order: ", Converter.toString(MathUtil.divide(totalamount, ComparisonUtil.nullIf(count, 0)))));
  			System.out.println(StringUtil.concat("Order processing finished at ", Converter.toString(TimeUtil.getDate())));
  			return outData;
  		}
  		finally {
  			outData.put("totalamount", totalamount);
  		}
  	}
  }