public Builder clearPooledInstances() {
          bitField0_ = (bitField0_ & ~0x00000020);
          pooledInstances_ = 0;
          onChanged();
          return this;
        }
<pre>
Output only. Number of instances currently available in the pool for
faster workstation startup.
</pre>

<code>int32 pooled_instances = 12 [(.google.api.field_behavior) = OUTPUT_ONLY];</code>

@return This builder for chaining.
java-workstations/proto-google-cloud-workstations-v1/src/main/java/com/google/cloud/workstations/v1/WorkstationConfig.java