Question

I am Trying to Read xml file of size 10 MB. I am Using Windows7 Operating system (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

I have tried C:\>java -Xms5120m -Xmx6144m But not helping.

StackTrace:

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

I suspect your 10 MB of data produces large amounts of graphical objects or other heavy weight objects. The simplest way to check is to add -XX+HeapDumpOnOutOfMemoryError and analyse where all the memory is being used.

You might like to reduce the maximum heap size so the dump is smaller as some tools (e.g. VisualVM) have difficulty loading large heap dumps.

Browsing a Heap Dump with VisualVM