Fields

Fields represent the data properties of your entities in LibEntity. Each field has a name, type, and can have validation rules, default values, and metadata. Fields are declared using the fluent DSL, making your entity definitions expressive and type-safe.

What is a Field?

A field is a property of your entity, such as amount, vat, or approverId. Fields can be of any Java type, including primitives, String, BigDecimal, enums, dates, and even custom objects.

Example: Declaring Fields

.field("amount", BigDecimal.class, f -> f
    .description("Invoice amount")
    .validateInState(InvoiceState.DRAFT, (state, entity, req, ctx) -> {
        if (entity.getAmount() == null || entity.getAmount().compareTo(BigDecimal.ZERO) <= 0) {
            ctx.addError("INVALID_AMOUNT", "Amount must be greater than zero");
        }
    })
)

Field Types

• Primitive types: int, boolean, etc.
• Common Java types: String, BigDecimal, LocalDate, etc.
• Enums: For controlled value sets
• Custom types: Your own classes

Field Validation

Fields can have validation logic attached, which is run in specific states or transitions.

Field Metadata

You can add descriptions, constraints, and even custom metadata to fields, improving documentation and API generation.