Library to generate Flow and JSDoc types from Java classes.

This library is for converting JavaBeans (data structures) to Flow/JSDoc types. It can be useful when developing software with Java backend and JavaScript (Flow/JSDoc) frontend.

Library uses Jackson to processing JavaBeans, JavaParser for reading JavaDoc from source classes, ASM for reading class retention annotations.

Example conversion

Java code:

/**
 * Dane o użytkowniku systemu.
 */
public class UserInfo {
    @NotNull
    public String id;
    @NotNull
    public String email;
    public String firstname;
    public String lastname;
}

/**
 * Klasa ze szczegółowymi informacjami o użytkowniku.
 */
public class UserData extends UserInfo {
    @JsonInclude(JsonInclude.Include.NON_NULL)
    public String orgId;

    @JsonInclude(JsonInclude.Include.NON_NULL)
    public String org;

    @JsonInclude(JsonInclude.Include.NON_NULL)
    public String orgNip;
}

Flow types:

/**
 * Dane o użytkowniku systemu.
 **/
export type UserInfo = {
    id: string;
    email: string;
    firstname: string|null;
    lastname: string|null;
};

/**
 * Klasa ze szczegółowymi informacjami o użytkowniku.
 **/
export type UserData = UserInfo & {
    orgId?: string|null;
    org?: string|null;
    orgNip?: string|null;
};

Installation

For now this library is in alpha stage, and it isn't published therefor for use it needs to be downloaded and installed locally to maven.

./gradlew publishToMavenLocal

Gradle plugin usage (recommended)

Library can be used to generate Flow types from Gradle. First (because library is not published) it Maven local repository needs to be added to plugin repositories (settings.gradle):

pluginManagement {
    repositories {
        mavenLocal()
        gradlePluginPortal()
    }
}

and now in build.gradle:

plugins {
    id 'java'
    id 'pl.rtprog.java2flow' version '0.0.3-SNAPSHOT'
}

java2flow {
    output = 'api.js'
    // provide classes to be transformed by name
    classes = [ 'pl.rtprog.pl.rtprog.java2flow.TestClass' ]
    // convert all classes is given packages
    packages = [ 'pl.rtprog.pl.rtprog.package2' ]  // 

}

Gradle plugin options:

• output - generated Flow types file name; default ${buildDir}/types.js,
• classes - array of class names to be converted to Flow types,
• packages - array of packages to convert classes that are in them to Flow types,
• flow - should Flow types be generated (default true),
• jsdoc - should JSDoc types be generated (default false).

Runtime usage

Library can be used in runtime to generate Flow types. To do so it needs to be added to dependencies (build.gradle):

repositories {
    mavenCentral()
    mavenLocal()    // this is needed
}

dependencies {
    implementation group: 'pl.rtprog', name: 'java2flow-core', version: '0.0.3-SNAPSHOT'
}

and then called from code:

Java2Flow c=new Java2Flow();
c.addHeader();
c.export(ClassToExport.class);
return c.toString();