如何解决线程“ AWT-EventQueue-0”中的异常java.lang.OutOfMemoryError：Java堆空间

Question

我正在尝试读取大小为10 MB的xml文件。 我正在使用Windows7操作系统（8GB RAM），Netbeans 7.1.2

    C:\>java -version
    java version "1.7.0_05"
    Java(TM) SE Runtime Environment (build 1.7.0_05-b05)
    Java HotSpot(TM) 64-Bit Server VM (build 23.1-b03, mixed mode)

C:\>free -m
             total       used       free     shared    buffers     cached
Mem:          8169       3175       4993          0          0          0
-/+ buffers/cache:       3175       4993
Swap:         8169         81       8087

我已经尝试过C:\\>java -Xms5120m -Xmx6144m但没有帮助。

堆栈跟踪：

Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap space
    at org.apache.xerces.xni.XMLString.toString(Unknown Source)
    at org.apache.xerces.parsers.AbstractDOMParser.characters(Unknown Source)
    at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanContent(Unknown Source)
    at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source)
    at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
    at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
    at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
    at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
    at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
    at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:208)
    at ReadExcel.xmlappend(ReadExcel.java:343)
    at ReadExcel.jButton7ActionPerformed(ReadExcel.java:331)
    at ReadExcel.access$600(ReadExcel.java:42)
    at ReadExcel$7.actionPerformed(ReadExcel.java:176)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
    at java.awt.Component.processMouseEvent(Component.java:6038)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3260)
    at java.awt.Component.processEvent(Component.java:5803)
    at java.awt.Container.processEvent(Container.java:2058)
    at java.awt.Component.dispatchEventImpl(Component.java:4410)
    at java.awt.Container.dispatchEventImpl(Container.java:2116)
    at java.awt.Component.dispatchEvent(Component.java:4240)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4322)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3986)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3916)
    at java.awt.Container.dispatchEventImpl(Container.java:2102)
    at java.awt.Window.dispatchEventImpl(Window.java:2429)

Answer 1

我怀疑您的10 MB数据会产生大量图形对象或其他重量级对象。 最简单的检查方法是添加-XX+HeapDumpOnOutOfMemoryError并分析正在使用所有内存的位置。

您可能希望减小最大堆大小，以使转储较小，因为某些工具（例如VisualVM）难以加载大堆转储。

使用VisualVM浏览堆转储