PL/I to Java Type Mapping

Name: type-mapping
Rating: 92
Author: comeredon

Character Types

PL/I	Java	Example
`CHAR(n)`	`String`	`private final String custId;`
`CHAR(1)`	`char`	`private final char recordType;`
`CHAR(n) VARYING`	`String`	Variable-length text

Decimal Types (always use BigDecimal for money)

PL/I	Java	Notes
`DEC(p,s)`	`BigDecimal`	Fixed decimal, e.g. DEC(7,2) = 7 digits, 2 decimal
`FIXED DEC(p,s)`	`BigDecimal`	Same as DEC

DEC(7,2) parsing: Stored as "0123456" → represents 1234.56

java

String balanceStr = line.substring(51, 58); // 7 bytes
String formatted = balanceStr.substring(0, 5) + "." + balanceStr.substring(5, 7);
BigDecimal balance = new BigDecimal(formatted);

Integer Types

PL/I	Java
`FIXED BIN(15)`	`short`
`FIXED BIN(31)`	`int`
`FIXED BIN(63)`	`long`

Other Types

PL/I	Java
`BIT(1)`	`boolean`
`PIC '9999'`	`int`
`PIC '99V99'`	`BigDecimal` (implied decimal)
Date `CHAR(8)`	`LocalDate` with `DateTimeFormatter`

Critical Rules

•Always use BigDecimal for monetary values (never double/float)
•Always wrap parseInt/parseLong in try-catch with sensible defaults
•Always validate record length before parsing
•Use substring(start, start + length) — end is exclusive