public String getField() {
        return this.field;
    }
<p>
The field to apply the placement strategy against. For the spread placement strategy, valid values are
<code>instanceId</code> (or <code>instanceId</code>, which has the same effect), or any platform or custom
attribute that is applied to a container instance, such as <code>attribute:ecs.availability-zone</code>. For the
binpack placement strategy, valid values are <code>cpu</code> and <code>memory</code>. For the random placement
strategy, this field is not used.
</p>

@return The field to apply the placement strategy against. For the spread placement strategy, valid values are
        <code>instanceId</code> (or <code>instanceId</code>, which has the same effect), or any platform or
        custom attribute that is applied to a container instance, such as
        <code>attribute:ecs.availability-zone</code>. For the binpack placement strategy, valid values are
        <code>cpu</code> and <code>memory</code>. For the random placement strategy, this field is not used.
aws-java-sdk-scheduler/src/main/java/com/amazonaws/services/scheduler/model/PlacementStrategy.java