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1
52
53 package com.go.trove.log;
54
55 import java.lang.ref.WeakReference  ;
56 import java.io.*;
57 import java.util.*;
58
59
69 public abstract class IntervalLogStream extends OutputStream {
70 private static int cCounter;
71
72 private static synchronized String nextName() {
73 return "IntervalLogStream Auto Rollover " + cCounter++;
74 }
75
76 private Factory mFactory;
77 private OutputStream mOut;
78 private boolean mIsClosed;
79
80 private Calendar mIntervalStart;
81 private Calendar mNextIntervalStart;
82
83 private Thread mRolloverThread;
84
85 public IntervalLogStream(Factory factory) {
86 mFactory = factory;
87 }
88
89
93 public synchronized void startAutoRollover() {
94 if (mRolloverThread == null) {
97 mRolloverThread = new Thread (new AutoRollover(this), nextName());
98 mRolloverThread.setDaemon(true);
99 mRolloverThread.start();
100 }
101 }
102
103
107 public synchronized void stopAutoRollover() {
108 if (mRolloverThread != null) {
109 mRolloverThread.interrupt();
110 mRolloverThread = null;
111 }
112 }
113
114
117 protected abstract void moveToIntervalStart(Calendar cal);
118
119
122 protected abstract void moveToNextIntervalStart(Calendar cal);
123
124 public synchronized void write(int b) throws IOException {
125 getOutputStream().write(b);
126 }
127
128 public synchronized void write(byte[] array) throws IOException {
129 getOutputStream().write(array, 0, array.length);
130 }
131
132 public synchronized void write(byte[] array, int off, int len)
133 throws IOException {
134
135 getOutputStream().write(array, off, len);
136 }
137
138 public synchronized void flush() throws IOException {
139 getOutputStream().flush();
140 }
141
142
146 public synchronized void close() throws IOException {
147 mIsClosed = true;
148 stopAutoRollover();
149
150 if (mOut != null) {
151 mOut.close();
152 }
153 }
154
155 protected synchronized void finalize() throws IOException {
156 close();
157 }
158
159 private synchronized OutputStream getOutputStream() throws IOException {
160 if (mIsClosed) {
161 throw new IOException("LogStream is closed");
162 }
163
164 Calendar cal = Calendar.getInstance();
165
166 if (mOut == null ||
167 cal.before(mIntervalStart) || !cal.before(mNextIntervalStart)) {
168
169 if (mOut != null) {
170 mOut.close();
171 }
172
173 mOut = new BufferedOutputStream
174 (mFactory.openOutputStream(cal.getTime()));
175
176 setIntervalEndpoints(cal);
177 }
178
179 return mOut;
180 }
181
182 private void setIntervalEndpoints(Calendar cal) {
183 mIntervalStart = (Calendar)cal.clone();
184 moveToIntervalStart(mIntervalStart);
185
186 mNextIntervalStart = cal;
187 moveToNextIntervalStart(mNextIntervalStart);
188 }
189
190 public static interface Factory {
191 public OutputStream openOutputStream(Date date) throws IOException;
192 }
193
194
198 private static class AutoRollover implements Runnable {
199 private WeakReference mLogStream;
202
203 public AutoRollover(IntervalLogStream stream) {
204 mLogStream = new WeakReference (stream);
205 }
206
207 public void run() {
208 try {
209 while (!Thread.interrupted()) {
210 IntervalLogStream stream =
211 (IntervalLogStream)mLogStream.get();
212
213 if (stream == null || stream.mIsClosed) {
214 break;
215 }
216
217 try {
218 stream.getOutputStream();
220 }
221 catch (IOException e) {
222 }
223
224 Calendar cal = Calendar.getInstance();
225 stream.moveToNextIntervalStart(cal);
226
227 stream = null;
230
231 long calTime = cal.getTime().getTime();
232 long timeLeft = calTime - System.currentTimeMillis();
233
234 while (timeLeft > 0) {
235 Thread.sleep(timeLeft);
237 timeLeft = calTime - System.currentTimeMillis();
238 }
239 }
240 }
241 catch (InterruptedException e) {
242 }
244 }
245 }
246 }
247 |
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