univocity-parsers

The Record interface allows you to export row data into various Map formats, which is useful for converting parsed rows into JSON or other object-based structures.

Map Types

• String Maps: Maps identifiers (headers, enums, or indices) to their String representation.
  • toFieldMap(String... selectedFields)
  • toIndexMap(int... selectedIndexes)
  • toEnumMap(Class<T> enumType, T... selectedColumns)
• Object Maps: Maps identifiers to the actual parsed object type (e.g., Integer, Date, etc.).
  • toFieldObjectMap(String... selectedFields)
  • toIndexObjectMap(int... selectedIndexes)
  • toEnumObjectMap(Class<T> enumType, T... selectedColumns)

If no specific fields are provided to the selection methods, the entire record is typically included.

// Convert specific fields to a Map of Strings
Map<String, String> fieldMap = record.toFieldMap("name", "email");

// Convert the whole record to a Map of Objects (parsed types)
Map<String, Object> objectMap = record.toFieldObjectMap();

// Convert using Enum columns
Map<MyEnum, Object> enumMap = record.toEnumObjectMap(MyEnum.class, MyEnum.COL_A, MyEnum.COL_B);

The RecordMetaData interface (implemented by RecordMetaDataImpl) allows you to access and convert data from individual records using several different identifiers: column names (String), column indexes (int), or Enum constants.

Key Capabilities

• Value Retrieval: Retrieve raw String values or converted objects from a record.
• Type Conversion: Automatically convert string data into specific types (e.g., Integer, Date, Boolean) using getObjectValue.
• Default Values: Define and retrieve default values for specific columns if the input data is null or missing.
• Format Specification: For types like Date, you can specify a format and options during retrieval.
• Column Metadata: Query the type or index of a column.

Supported Identifiers

Most methods accept one of the following to identify a column:

• int columnIndex
• String headerName
• Enum<?> column

// Example: Retrieving a value with conversion and a default value
Integer age = recordMetaData.getObjectValue(rowData, "age", Integer.class, 0);

// Example: Retrieving a Date with a specific format
Date date = recordMetaData.getObjectValue(rowData, "created_at", Date.class, "yyyy-MM-dd", "HH:mm:ss");

// Example: Using an Enum for column identification
String status = recordMetaData.getValue(rowData, StatusEnum.STATUS_COLUMN);

The Record interface provides a high-level API to retrieve data from a single parsed row. You can access values using three different identifiers: a header name (String), an enum column (Enum<?>), or a column index (int).

Type-Safe Value Retrieval

You can retrieve values as specific types. The library handles the conversion from the raw string data to the requested type.

• Generic Retrieval: Use getValue(identifier, expectedType) to get a value of a specific class.
• Default Values: Use getValue(identifier, defaultValue) to return a provided default if the value is missing or null.
• Custom Conversions: Use getValue(identifier, expectedType, Conversion...) to apply specific Conversion logic during retrieval.

Specialized Type Getters

For convenience, the interface provides direct methods for common types:

• getString(identifier)
• getInt(identifier), getLong(identifier), getShort(identifier), getByte(identifier)
• getFloat(identifier), getDouble(identifier)
• getBoolean(identifier) (supports custom trueString and falseString mapping)
• getBigDecimal(identifier), getBigInteger(identifier)
• getDate(identifier), getCalendar(identifier)
• getChar(identifier), getBoolean(identifier)

Formatted Retrieval

For numeric and date types, you can pass a format string and optional format options to handle specific parsing requirements: getInteger(identifier, format, formatOptions...)

// Example: Accessing values by header name
String name = record.getString("name");
int age = record.getInt("age");
BigDecimal salary = record.getBigDecimal("salary");

// Example: Accessing values with a default value
String city = record.getValue("city", "Unknown");

// Example: Accessing values by index
String firstCol = record.getString(0);

// Example: Boolean with custom true/false strings
boolean isActive = record.getBoolean("active", "YES", "NO");