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Thread: How to solve OutOfMemoryException using arraylist & hashmap

  1. #1
    Junior Member
    Join Date
    Apr 2013
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    Question How to solve OutOfMemoryException using arraylist & hashmap

    Hi Experts,

    Its really very strange issue in our end. In our application we have stored the map with arraylist. Sometimes if the values grows OOME is thrown.
    I have searched a lot but haven't no idea to rectify this problem. So if you have anything i will try this in our end.

    I have attached the sample code for we are using the way

    public class JavaOutOfMemoryHandling

    public static void main(String arg[])
    ArrayList thresholdElements = null;

    // List of data's
    for (int i = 0; i < 500000; ++i)
    HashMap threshMap = new HashMap(5);
    threshMap.put("THRESHOLD", "SampleThreshold_"+i);
    threshMap.put("ENTITY", "SampleEntityID_"+i);
    threshMap.put("MO", "SampleMOID_"+i) ;
    threshMap.put("NAME", "SampleName_"+i);
    threshMap.put("DISPLAY", "SampleDisplayName_"+i);
    if (thresholdElements == null)
    thresholdElements = new ArrayList(5);

    // this should shrink the array back to a decent size
    System.out.println("ArrayList :: "+thresholdElements);



    Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
    at java.lang.AbstractStringBuilder.expandCapacity(Abs tractStringBuilder.java:99)
    at java.lang.AbstractStringBuilder.append(AbstractStr ingBuilder.java:393)
    at java.lang.StringBuffer.append(StringBuffer.java:22 5)
    at java.util.AbstractCollection.toString(AbstractColl ection.java:454)
    at java.lang.String.valueOf(String.java:2615)
    at java.lang.StringBuilder.append(StringBuilder.java: 116)
    at JavaOutOfMemoryHandling.main(JavaOutOfMemoryHandli ng.java:33)

    Please give some idea to rectify OOME.

    Thanks & Regards,
    Karpahasundaram M.[/size]

  2. #2
    Senior Member PhHein's Avatar
    Join Date
    Mar 2013
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    Thanked 93 Times in 86 Posts

    Default Re: How to solve OutOfMemoryException using arraylist & hashmap

    Apart from the strange architecture, you can configure the memory settings of the VM. Tuning Java Virtual Machines (JVMs)

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