String value holders: useful or memory hogs?

From: Oliver Plohmann (oliver_at_plohmann.com)
Date: 10/30/04

  • Next message: Stefan Schulz: "Re: why URLConnection is declared abstract" 
    Date: 30 Oct 2004 12:19:33 -0700

    I have a lot of collections in my application that hold strings which
    represent objects. These objects are often on remote machines, which
    is the reason why I plug in their id strings into some collections
    instead of the objects themselves. This makes it possible that coding
    errors may happen, which the compiler cannot find. Example:

    List<String> nodeIds = new Array<String>();
    List<String> agentIds = new Array<String>();

    String nodeId = "uniqueNodeId";
    agentIds.add(nodeId); // logical coding error and compiler would not
    complain

    The compiler would find these kind of errors if string value holders
    were used:

    public class NodeId {

        protected String id = null;
        // remaining code omitted for brevity
    }

    public class AgentId {

        protected String id = null;
        // remaining code omitted for brevity
    }

    List<NodeId> nodeIds = new Array<NodeId>();
    List<AgentId> agentIds = new Array<AgentId>();

    NodeId nodeId = new NodeId("uniqueNodeId");
    agentIds.add(nodeId); // ==> compiler error !!

    Now I'm expecting memory consumption to raise because of these value
    holder classes like NodeId and AgentId. I wonder whether it will make
    a difference. I guess so, but I wonder how much. Did any body out
    there already try something similar and has some recommendations?

    Thanx for any feed-back,
    Oliver

  • Next message: Stefan Schulz: "Re: why URLConnection is declared abstract"

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