public void setLastChangedAt(java.util.Date lastChangedAt) {
        this.lastChangedAt = lastChangedAt;
    }
<p>
The timestamp when the transition state was last changed.
</p>

@param lastChangedAt
       The timestamp when the transition state was last changed.
aws-java-sdk-codepipeline/src/main/java/com/amazonaws/services/codepipeline/model/TransitionState.java