Class MongoDBSubStringFunction

java.lang.Object

com.kingsrook.qqq.backend.module.mongodb.fieldfunctions.MongoDBSubStringFunction

All Implemented Interfaces:

BackendFieldFunctionAdapterInterface, MongoDBFieldFunctionAdapterInterface, Serializable

public class MongoDBSubStringFunction
extends Object
implements MongoDBFieldFunctionAdapterInterface

MongoDB adapter for SubStringFunction. Generates {$substrCP: ["$field", fromIndex, length]}. MongoDB $substrCP is 0-based; QQQ SubStringFunction uses 1-based (like SQL). When no length is specified, uses Integer.MAX_VALUE as a sentinel.

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
MongoDBSubStringFunction()

Method Summary

Modifier and Type	Method	Description
Object	getExpression(String fieldReference, FieldFunction fieldFunction, Function<String,String> fieldNameToFieldReference)	Returns a MongoDB aggregation expression for the given field reference.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.kingsrook.qqq.backend.module.mongodb.fieldfunctions.MongoDBFieldFunctionAdapterInterface

getExpressionForOrderBy

Constructor Details

MongoDBSubStringFunction

public MongoDBSubStringFunction()

Method Details

getExpression

public Object getExpression(String fieldReference,
 FieldFunction fieldFunction,
 Function<String,String> fieldNameToFieldReference)

Description copied from interface: MongoDBFieldFunctionAdapterInterface

Returns a MongoDB aggregation expression for the given field reference. The fieldReference is a "$"-prefixed field name (e.g., "$firstName").

Specified by:

getExpression in interface MongoDBFieldFunctionAdapterInterface

Parameters:

fieldReference - "$"-prefixed field name for the function's source field.

fieldFunction - the function with arguments.

fieldNameToFieldReference - resolves a QQQ field name to its "$"-prefixed MongoDB field reference (e.g., "timeZone" → "$time_zone"). Useful when the function expression needs to reference additional fields on the same document (e.g., a per-row timezone field).