001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.hbtop.screen.top; 019 020import java.util.Objects; 021import org.apache.hadoop.hbase.hbtop.field.Field; 022import org.apache.yetus.audience.InterfaceAudience; 023 024/** 025 * Represents headers for the metrics in the top screen. 026 */ 027@InterfaceAudience.Private 028public class Header { 029 private final Field field; 030 private final int length; 031 032 public Header(Field field, int length) { 033 this.field = Objects.requireNonNull(field); 034 this.length = length; 035 } 036 037 public String format() { 038 return "%" + (field.isLeftJustify() ? "-" : "") + length + "s"; 039 } 040 041 public Field getField() { 042 return field; 043 } 044 045 public int getLength() { 046 return length; 047 } 048}