Question

我反复使用Jackson的writeValueAsString方法将一个对象转换为String，就像重复进行数千次一样。 JSON的大小约为1KB。但是过了一会儿，我的程序退出并抛出OOM异常。以下是堆栈跟踪：

Exception in thread "main" java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:87)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:50)
        at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:51)
Caused by: java.lang.OutOfMemoryError: Java heap space
        at com.fasterxml.jackson.core.util.TextBuffer.carr(TextBuffer.java:864)
        at com.fasterxml.jackson.core.util.TextBuffer.expand(TextBuffer.java:825)
        at com.fasterxml.jackson.core.util.TextBuffer.append(TextBuffer.java:590)
        at com.fasterxml.jackson.core.io.SegmentedStringWriter.write(SegmentedStringWriter.java:58)
        at com.fasterxml.jackson.core.json.WriterBasedJsonGenerator._writeString2(WriterBasedJsonGenerator.java:1013)
        at com.fasterxml.jackson.core.json.WriterBasedJsonGenerator._writeString(WriterBasedJsonGenerator.java:982)
        at com.fasterxml.jackson.core.json.WriterBasedJsonGenerator.writeString(WriterBasedJsonGenerator.java:377)
        at com.fasterxml.jackson.databind.ser.std.StringSerializer.serialize(StringSerializer.java:41)
        at com.fasterxml.jackson.databind.ser.std.MapSerializer.serializeFields(MapSerializer.java:718)
        at com.fasterxml.jackson.databind.ser.std.MapSerializer.serialize(MapSerializer.java:639)
        at com.fasterxml.jackson.databind.ser.std.MapSerializer.serialize(MapSerializer.java:33)
        at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:480)
        at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:319)
        at com.fasterxml.jackson.databind.ObjectMapper._configAndWriteValue(ObjectMapper.java:3893)
        at com.fasterxml.jackson.databind.ObjectMapper.writeValueAsString(ObjectMapper.java:3207)
        at com.ad2pro.neonmigration.neondatamigration.utils.NeonMetricsProducerUtil.produceImpressions(NeonMetricsProducerUtil.java:121)
        at com.ad2pro.neonmigration.neondatamigration.scheduler.NeonScheduler.gerMetrics(NeonScheduler.java:100)
        at com.ad2pro.neonmigration.neondatamigration.NeonDataMigrationApplication.main(NeonDataMigrationApplication.java:18)
        ... 8 more
java.lang.OutOfMemoryError: Java heap space
        at javax.crypto.CipherSpi.bufferCrypt(CipherSpi.java:814)
        at javax.crypto.CipherSpi.engineUpdate(CipherSpi.java:555)
        at javax.crypto.Cipher.update(Cipher.java:2002)
        at sun.security.ssl.CipherBox.decrypt(CipherBox.java:544)
        at sun.security.ssl.EngineInputRecord.decrypt(EngineInputRecord.java:200)
        at sun.security.ssl.SSLEngineImpl.readRecord(SSLEngineImpl.java:974)
        at sun.security.ssl.SSLEngineImpl.readNetRecord(SSLEngineImpl.java:907)
        at sun.security.ssl.SSLEngineImpl.unwrap(SSLEngineImpl.java:781)
        at javax.net.ssl.SSLEngine.unwrap(SSLEngine.java:624)
        at com.amazon.support.channels.TLSSocketChannel.read(Unknown Source)
        at com.amazon.jdbc.communications.InboundMessagesThread.run(Unknown Source)
~

程序启动前有1GB的可用内存。 objectmapper是否占用大量内存，即使1GB内存也不足以将对象转换为String。任何帮助表示赞赏。

Answer 1

您可以尝试通过参数-Xmx和-Xms设置JVM堆。例如，告诉Jvm最多使用512 mb -Xms512m堆。

默认的最大堆大小为64 mb，可能对您的程序来说还不够。

Objectmapper writeValueAsString引发OOM异常

1 个答案: