How to Check if a Java ResultSet Has Results Without `hasNext()`?

Checking the Presence of Results in a Java ResultSet

When working with a Java ResultSet, it is essential to determine whether it contains any results before proceeding with further operations.

Question: How can I verify if a ResultSet has any value, given that it lacks a hasNext() method?

Answer:

The correct approach is indeed to use the !resultSet.next() condition. However, a simplified solution that avoids potential cursor tracking issues is to utilize the isBeforeFirst() method:

if (!resultSet.isBeforeFirst() ) {    
    System.out.println("No data"); 
} 

As indicated in the JDBC documentation, isBeforeFirst() returns false when the cursor is not before the first record or if the ResultSet is empty. This eliminates the need to backtrack through the results if data is present.

By implementing either of these methods, you can efficiently check for the presence of results in a ResultSet.

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