001/* 002 * Copyright 2002-2018 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.core.io.support; 018 019import org.springframework.core.io.Resource; 020import org.springframework.util.Assert; 021 022/** 023 * Region of a {@link Resource} implementation, materialized by a {@code position} 024 * within the {@link Resource} and a byte {@code count} for the length of that region. 025 * 026 * @author Arjen Poutsma 027 * @since 4.3 028 */ 029public class ResourceRegion { 030 031 private final Resource resource; 032 033 private final long position; 034 035 private final long count; 036 037 038 /** 039 * Create a new {@code ResourceRegion} from a given {@link Resource}. 040 * This region of a resource is represented by a start {@code position} 041 * and a byte {@code count} within the given {@code Resource}. 042 * @param resource a Resource 043 * @param position the start position of the region in that resource 044 * @param count the byte count of the region in that resource 045 */ 046 public ResourceRegion(Resource resource, long position, long count) { 047 Assert.notNull(resource, "Resource must not be null"); 048 Assert.isTrue(position >= 0, "'position' must be larger than or equal to 0"); 049 Assert.isTrue(count >= 0, "'count' must be larger than or equal to 0"); 050 this.resource = resource; 051 this.position = position; 052 this.count = count; 053 } 054 055 056 /** 057 * Return the underlying {@link Resource} for this {@code ResourceRegion}. 058 */ 059 public Resource getResource() { 060 return this.resource; 061 } 062 063 /** 064 * Return the start position of this region in the underlying {@link Resource}. 065 */ 066 public long getPosition() { 067 return this.position; 068 } 069 070 /** 071 * Return the byte count of this region in the underlying {@link Resource}. 072 */ 073 public long getCount() { 074 return this.count; 075 } 076 077}