<input type="text" class="form-control" name="writer" [value]="writer" placeholder="글쓴이" *ngIf="writer; else writable" readonly/>
<ng-template #writable>
<input type="text" class="form-control" name="writer" placeholder="글쓴이"/>
</ng-template>
이게 ngif쓴건데
jstl로 쓰면
<c:if test={!empty writer}>
<input type="text" class="form-control" name="writer" value="{writer}"placeholder="글쓴이"/>
<c:if>
<c:if test={empty writer>
<input type="text" class="form-control" name="writer" placeholder="글쓴이" readonly/>
<c:if>
이게 훨신 가독성 좋은거같음;;
하단 스타일을 원하면 ngIf에도 else문대신 !로 하면 됨