Last active
March 29, 2019 00:14
-
-
Save pereira-a/ab357581495f7a9394c8bce43055a19f to your computer and use it in GitHub Desktop.
Convert a SQL ResultSet to json format
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
import com.fasterxml.jackson.databind.JsonNode; | |
import com.fasterxml.jackson.databind.ObjectMapper; | |
import com.fasterxml.jackson.databind.node.ArrayNode; | |
import com.fasterxml.jackson.databind.node.ObjectNode; | |
import java.sql.ResultSet; | |
import java.sql.ResultSetMetaData; | |
import java.sql.SQLException; | |
public class ResultsetConverter { | |
public static JsonNode convertToJson(ResultSet rs){ | |
if(rs == null) return null; | |
ObjectMapper mapper = new ObjectMapper(); | |
try { | |
ResultSetMetaData rsmd = rs.getMetaData(); | |
ObjectNode first = null; | |
ArrayNode array = null; | |
if(rs.next()){ | |
first = getObjectNode(rs, mapper, rsmd); | |
} | |
while(rs.next()){ | |
if(array == null){ | |
array = mapper.createArrayNode(); | |
array.add(first); | |
} | |
array.add(getObjectNode(rs, mapper, rsmd)); | |
} | |
return array == null ? first : array; | |
} catch (SQLException e) { | |
e.printStackTrace(); | |
return null; | |
} | |
} | |
private static ObjectNode getObjectNode(ResultSet rs, ObjectMapper mapper, ResultSetMetaData rsmd){ | |
ObjectNode obj = mapper.createObjectNode(); | |
try { | |
int columnCount = rsmd.getColumnCount(); | |
for(int i = 1; i <= columnCount; i++){ | |
String column = rsmd.getColumnName(i); | |
Object value = rs.getObject(i); | |
if(value == null){ | |
obj.putNull(column); | |
}else if(value instanceof String){ | |
obj.put(column, (String) value); | |
}else if(value instanceof Integer){ | |
obj.put(column, (Integer) value); | |
}else { | |
throw new IllegalArgumentException("Unmappable object type: " + value.getClass()); | |
} | |
} | |
} catch (SQLException e) { | |
e.printStackTrace(); | |
} | |
return obj; | |
} | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment