docs / stdlib / aot

Scoped

cajeta.aot.Scoped<T> is a handle on a scoped component, injected where the holder outlives the component’s scope. A field may hold only a component that outlives its holder, so a singleton that needs a request’s component injects the handle and resolves it where it is needed.

import cajeta.aot.Scoped;

@Component(scope = "Order")
public class Budget {
    public int32 left;
    public Budget() { this.left = 10; return; }
}

@Component
public class Spender {
    @Inject Scoped<Budget> budget;
    public Spender() { return; }
    public int32 spend(int32 n) {
        Budget b = this.budget.get();
        b.left = b.left - n;
        return b.left;
    }
}

public final class Calls {
    @Scope("Order")
    public static int32 once(int32 n) {
        Spender s = Spender.__cajeta_inject();
        return s.spend(n);
    }
}

Methods

get() outside every activation of the scope throws ScopeNotActiveException. The holder owns the handle, and the handle owns nothing.

See also

• Scope, Components
• Source: runtime/src/cajeta/aot/Scoped.cajeta

Source: docs/stdlib/aot/Scoped.md · 1 min read · 98 words