CREATE JAVA ACTION

Synopsis

CREATE [ OR MODIFY ] JAVA ACTION module.Name ( parameters )
    RETURNS type
    [ EXPOSED AS 'caption' IN 'category' ]
    AS $$ java_code $$

DROP JAVA ACTION module.Name

Description

Creates a Java action with inline Java code. Java actions allow custom server-side logic written in Java to be called from microflows.

The action parameters, return type, and Java body are all specified inline. When the action is created, the corresponding Java source file is generated with the parameter boilerplate and the provided code body.

The AS $$ ... $$ body is mandatory. Unlike microflows, Java actions require a code body in every CREATE statement. If the body is omitted the parser reports no viable alternative at input '...'. Use a minimal stub body if the implementation is not yet written: AS $$ return false; $$.

If OR MODIFY is specified and the Java action already exists, its parameters, return type, exposed-as settings, and Java body are updated in place. The UUID and any existing Java source file path are preserved.

Type Parameters

Java actions support generic entity handling through type parameters. A parameter declared as ENTITY <pEntity> creates a type parameter selector – the caller chooses which entity type to use. Other parameters declared as bare pEntity (without ENTITY) receive instances of the selected entity type.

Exposed Actions

The optional EXPOSED AS clause makes the action visible in the Studio Pro toolbox under the specified category, allowing modelers to use it directly in microflows.

Parameters

module.Name

The qualified name of the Java action.

parameters

Comma-separated parameter declarations. Each parameter has a name, colon, and type. Supported types:

Primitives: String, Integer, Long, Decimal, Boolean, DateTime
Entity: Module.EntityName
List: List of Module.EntityName
Enumeration: ENUM Module.EnumName or Enumeration(Module.EnumName)
String template: StringTemplate(Sql), StringTemplate(Oql)
Type parameter declaration: ENTITY <pEntity> (declares the type parameter)
Type parameter reference: bare pEntity (uses the declared type parameter)
Add NOT NULL after the type to mark a parameter as required.

RETURNS type

The return type. Same type options as parameters.

EXPOSED AS 'caption' IN 'category'

Optional. Makes the action visible in the toolbox with the given caption and category.

AS $$ java_code $$

The Java code body, enclosed in $$ delimiters. Mandatory — the body cannot be omitted.

OR MODIFY

Makes the statement idempotent. If the Java action already exists, updates its parameters, return type, exposed-as settings, and body. Without this clause, creating a duplicate Java action is an error.

Examples

Simple Java action returning a string:

CREATE JAVA ACTION MyModule.JA_FormatCurrency (
    Amount: Decimal NOT NULL,
    CurrencyCode: String NOT NULL
) RETURNS String
AS $$
    java.text.NumberFormat formatter = java.text.NumberFormat.getCurrencyInstance();
    formatter.setCurrency(java.util.Currency.getInstance(CurrencyCode));
    return formatter.format(Amount);
$$;

Java action with type parameters for generic entity handling:

CREATE JAVA ACTION MyModule.JA_Validate (
    EntityType: ENTITY <pEntity> NOT NULL,
    InputObject: pEntity NOT NULL
) RETURNS Boolean
EXPOSED AS 'Validate Entity' IN 'Validation'
AS $$
    return InputObject != null;
$$;

Java action with a list parameter:

CREATE JAVA ACTION MyModule.JA_ExportToCsv (
    Records: List of MyModule.Customer NOT NULL,
    FilePath: String NOT NULL
) RETURNS Boolean
AS $$
    // Export logic here
    return true;
$$;

Drop a Java action:

DROP JAVA ACTION MyModule.JA_FormatCurrency;

Idempotent upsert with OR MODIFY

-- Initial creation
CREATE JAVA ACTION MyModule.JA_FormatCurrency (
    Amount: Decimal NOT NULL,
    CurrencyCode: String NOT NULL
) RETURNS String
AS $$
    return Amount.toString();
$$;

-- Later: update to add proper formatting (UUID preserved)
CREATE OR MODIFY JAVA ACTION MyModule.JA_FormatCurrency (
    Amount: Decimal NOT NULL,
    CurrencyCode: String NOT NULL
) RETURNS String
AS $$
    java.text.NumberFormat formatter = java.text.NumberFormat.getCurrencyInstance();
    formatter.setCurrency(java.util.Currency.getInstance(CurrencyCode));
    return formatter.format(Amount);
$$;

Minimal stub body

When a Java action needs to exist in the project but the implementation is not yet written:

CREATE JAVA ACTION MyModule.JA_Placeholder (
    Input: String NOT NULL
) RETURNS Boolean
AS $$ return false; $$;

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