@Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("{");
        if (getSourceUserIdentifier() != null)
            sb.append("SourceUserIdentifier: ").append(getSourceUserIdentifier()).append(",");
        if (getDestinationUserIdentifier() != null)
            sb.append("DestinationUserIdentifier: ").append(getDestinationUserIdentifier()).append(",");
        if (getDeveloperProviderName() != null)
            sb.append("DeveloperProviderName: ").append(getDeveloperProviderName()).append(",");
        if (getIdentityPoolId() != null)
            sb.append("IdentityPoolId: ").append(getIdentityPoolId());
        sb.append("}");
        return sb.toString();
    }
Returns a string representation of this object. This is useful for testing and debugging. Sensitive data will be
redacted from this string using a placeholder value.

@return A string representation of this object.

@see java.lang.Object#toString()
aws-java-sdk-cognitoidentity/src/main/java/com/amazonaws/services/cognitoidentity/model/MergeDeveloperIdentitiesRequest.java