...
| Code Block | ||
|---|---|---|
| ||
class SensorData implements Serializable {
// 1MB of data per instance!
...
public static SensorData readSensorData() {...}
public static boolean continueReading() {...}
}
class SerializeSensorData {
public static void main(String[] args) throws IOException {
ObjectOutputStream out = null;
try {
out = new ObjectOutputStream(
new BufferedOutputStream(new FileOutputStream("ser.dat")));
while (SensorData.continueReading()) {
// note that each SensorData object is 1MB in size
SensorData sd = SensorData.readSensorData();
out.writeObject(sd);
}
} finally {
out.close();
}
}
}
|
Compliant Solution
This compliant solution takes advantage of the known properties of the sensor data by resetting the output stream after each write. The reset clears the output stream's internal object cache; consequently, the cache no longer maintains references to previously-written SensorData objects. The garbage collector is able to collect SensorData instances that are no longer needed.
| Code Block | ||
|---|---|---|
| ||
class SerializeSensorData {
public static void main(String[] args) throws IOException {
ObjectOutputStream out = null;
try {
out = new ObjectOutputStream(
new BufferedOutputStream(new FileOutputStream("ser.dat")));
while (SensorData.continueReading()) {
// note that each SensorData object is 1MB in size
SensorData sd = SensorData.readSensorData();
out.writeObject(sd);
out.reset(); // reset the stream
}
} finally {
out.close();
}
}
}
|
Risk Assessment
Memory and resource leaks during serialization can consume all available memory or crash the JVM.
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| ]]></ac:plain-text-body></ac:structured-macro> |
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="0eba6c9dc5828fa4-53c6ccac-4a054a1a-a6b8ab00-d12177564427a6263ffb08d8"><ac:plain-text-body><![CDATA[ | [[Harold 2006 | AA. Bibliography#Harold 06]] | 13.4. Performance | ]]></ac:plain-text-body></ac:structured-macro> |
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="b3d8b8485ee1ee31-9c1ef245-4c324300-bfc48ae4-90c310aa559946438e8b61c4"><ac:plain-text-body><![CDATA[ | [[Sun 2006 | AA. Bibliography#Sun 06]] | "Serialization specification" | ]]></ac:plain-text-body></ac:structured-macro> |
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