Function generateRpcRootFile

java/scripts/codegen/java.ts:1875–2006

* Generate ServerRpc.java or SessionRpc.java — the top-level wrapper class.

(
    sectionName: string, // "server" | "session"
    tree: NamespaceTree,
    isSession: boolean,
    packageName: string,
    packageDir: string
)

 * Generate ServerRpc.java or SessionRpc.java — the top-level wrapper class.
 */
async function generateRpcRootFile(
    sectionName: string, // "server" | "session"
    tree: NamespaceTree,
    isSession: boolean,
    packageName: string,
    packageDir: string
): Promise<void> {
    const prefix = sectionName === "server" ? "Server" : "Session";
    const rootClassName = prefix + "Rpc";
    const sessionIdExpr = "this.sessionId";

    const classLines: string[] = [];
    const allImports = new Set<string>([
        "java.util.concurrent.CompletableFuture",
        "javax.annotation.processing.Generated",
    ]);
    let needsMapper = false;

    // Sub-namespace fields and init lines
    const subFields: string[] = [];
    const subInits: string[] = [];
    for (const [nsKey, nsTree] of tree.subspaces) {
        const nsClass = apiClassName(prefix, [nsKey]);
        subFields.push(`    /** API methods for the {@code ${nsKey}} namespace. */`);
        subFields.push(`    public final ${nsClass} ${nsKey};`);
        if (isSession) {
            subInits.push(`        this.${nsKey} = new ${nsClass}(caller, sessionId);`);
        } else {
            subInits.push(`        this.${nsKey} = new ${nsClass}(caller);`);
        }
        // Generate the namespace API class file (recursively)
        await generateNamespaceApiFile(prefix, [nsKey], nsTree, isSession, packageName, packageDir);
    }

    // Collect result/param imports and generate top-level method bodies
    const methodLines: string[] = [];
    for (const [key, method] of tree.methods) {
        const resultClass = wrapperResultClassName(method);
        const paramsClass = wrapperParamsClassName(method);
        addWrapperResultImports(resultClass, allImports, packageName);
        if (paramsClass) allImports.add(`${packageName}.${paramsClass}`);

        const { lines, needsMapper: nm, needsExperimentalImport } = generateApiMethod(key, method, isSession, sessionIdExpr);
        methodLines.push(...lines);
        if (nm) needsMapper = true;
        if (needsExperimentalImport) allImports.add("com.github.copilot.CopilotExperimental");
    }

    // Build file content
    classLines.push(COPYRIGHT);
    classLines.push(``);
    classLines.push(AUTO_GENERATED_HEADER);
    classLines.push(GENERATED_FROM_API);
    classLines.push(``);
    classLines.push(`package ${packageName};`);
    classLines.push(``);

    const sortedImports = [...allImports].filter(imp => !imp.startsWith(packageName + ".")).sort();