public Builder setTargetResource(java.lang.String value) {
      if (value == null) {
        throw new NullPointerException();
      }
      targetResource_ = value;
      bitField0_ |= 0x00000010;
      onChanged();
      return this;
    }
<pre>
Required. Immutable. The Google Workspace resource that's monitored for
events, formatted as the [full resource
name](https://google.aip.dev/122#full-resource-names). To learn about
target resources and the events that they support, see [Supported Google
Workspace
events](https://developers.google.com/workspace/events#supported-events).

A user can only authorize your app to create one subscription for a given
target resource. If your app tries to create another subscription with the
same user credentials, the request returns an `ALREADY_EXISTS` error.
</pre>

<code>
string target_resource = 4 [(.google.api.field_behavior) = IMMUTABLE, (.google.api.field_behavior) = REQUIRED, (.google.api.resource_reference) = { ... }
</code>

@param value The targetResource to set.
@return This builder for chaining.
java-workspaceevents/proto-google-cloud-workspaceevents-v1/src/main/java/com/google/apps/events/subscriptions/v1/Subscription.java