001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.activemq.kaha.impl.async;
018
019 import java.io.File;
020 import java.io.IOException;
021 import java.io.RandomAccessFile;
022
023 import org.apache.activemq.util.IOHelper;
024 import org.apache.activemq.util.LinkedNode;
025
026 /**
027 * DataFile
028 *
029 *
030 */
031 public class DataFile extends LinkedNode implements Comparable<DataFile> {
032
033 protected final File file;
034 protected final Integer dataFileId;
035 protected final int preferedSize;
036
037 protected int length;
038 protected int referenceCount;
039
040 DataFile(File file, int number, int preferedSize) {
041 this.file = file;
042 this.preferedSize = preferedSize;
043 this.dataFileId = Integer.valueOf(number);
044 length = (int)(file.exists() ? file.length() : 0);
045 }
046
047 File getFile() {
048 return file;
049 }
050
051 public Integer getDataFileId() {
052 return dataFileId;
053 }
054
055 public synchronized int getLength() {
056 return length;
057 }
058
059 public void setLength(int length) {
060 this.length = length;
061 }
062
063 public synchronized void incrementLength(int size) {
064 length += size;
065 }
066
067 public synchronized int increment() {
068 return ++referenceCount;
069 }
070
071 public synchronized int decrement() {
072 return --referenceCount;
073 }
074
075 public synchronized int getReferenceCount(){
076 return referenceCount;
077 }
078
079 public synchronized boolean isUnused() {
080 return referenceCount <= 0;
081 }
082
083 public synchronized String toString() {
084 String result = file.getName() + " number = " + dataFileId + " , length = " + length + " refCount = " + referenceCount;
085 return result;
086 }
087
088 public synchronized RandomAccessFile openRandomAccessFile(boolean appender) throws IOException {
089 RandomAccessFile rc = new RandomAccessFile(file, "rw");
090 // When we start to write files size them up so that the OS has a chance
091 // to allocate the file contiguously.
092 if (appender) {
093 if (length < preferedSize) {
094 try {
095 // this can throw if we run out of disk space
096 rc.setLength(preferedSize);
097 } catch (IOException ioe) {
098 try {
099 rc.close();
100 } catch(Exception ignored) {
101 }
102 throw ioe;
103 }
104 }
105 }
106 return rc;
107 }
108
109 public synchronized void closeRandomAccessFile(RandomAccessFile file) throws IOException {
110 // On close set the file size to the real size.
111 if (length != file.length()) {
112 file.setLength(getLength());
113 }
114 file.close();
115 }
116
117 public synchronized boolean delete() throws IOException {
118 return file.delete();
119 }
120
121 public synchronized void move(File targetDirectory) throws IOException{
122 IOHelper.moveFile(file,targetDirectory);
123 }
124
125 public int compareTo(DataFile df) {
126 return dataFileId - df.dataFileId;
127 }
128
129 @Override
130 public boolean equals(Object o) {
131 boolean result = false;
132 if (o instanceof DataFile) {
133 result = compareTo((DataFile)o) == 0;
134 }
135 return result;
136 }
137
138 @Override
139 public int hashCode() {
140 return dataFileId;
141 }
142 }