resources.report.rules.findbugs.EMF_BAD_ASSIGNMENT.html Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of sanity4j Show documentation

Sanity4J was created to simplify running multiple static code analysis tools on the Java projects. It provides a single entry point to run all the selected tools and produce a consolidated report, which presents all findings in an easily accessible manner.

There is a newer version: 1.8.2

Show newest version



EMF: Bad Assignment (EMF_BAD_ASSIGNMENT)


EMF: Bad Assignment (EMF_BAD_ASSIGNMENT)

Investigation of production WebSphere Portal 
Java Heap Dumps revealed that HTTP sessions
were "hanging on" to a large number of EMF types (which use
up a lot of memory) within the Portal applications.  Tracking back 
some Java reference chains within the heapdumps, this seems to be 
due to some accidental "shallow copying" of some of the Lists 
returned within the SDOs. i.e.

	modelObject.setStringList(sdo.getStringList()) 


and

	public void setStringList(final List stringList) {
		this.stringList = stringList;
	}


type behaviour, rather than:

	modelObject.setStringList(new ArrayList(sdo.getStringList());


or


	public void setStringList(final List stringList) {
		this.stringList = new ArrayList(stringList);
	}


(etc... for more complicated object lists...)

The first example is causing the model object to store 
a reference to an EMF EcoreEList rather than a simple list
of Strings. Because the EcoreEList maintains a reference 
to its "owning" object, which via another set of references 
means that the entire SDO from which this list was obtained 
stays in memory.