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POSet of custom objects contains the same object
 

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  1. POSet of custom objects contains the same object
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    <p>I am seeing some weird behaviour of Java <code>Set</code>. Here is the very simple code snippet I'm having issues with:</p> <pre><code>public Set&lt;StopSequence&gt; reduce() { Set&lt;StopSequence&gt; stopSequences = new HashSet&lt;StopSequence&gt;(); StopSequence currentSequence = null; for (StopTime stopTime: mStopTimes) { if (stopTime.getStopSequence() == 0) { //beginning of a new sequence if (currentSequence != null) { if (stopSequences.add(currentSequence)) { System.out.println("Added sequence:"); System.out.println(currentSequence.toString()); } currentSequence.clear(); } else { currentSequence = new StopSequence(); } currentSequence.add(stopTime.getStopId()); } else { currentSequence.add(stopTime.getStopId()); } } Iterator&lt;StopSequence&gt; iterator = stopSequences.iterator(); while (iterator.hasNext()) { System.out.println(iterator.next()); } return stopSequences; } </code></pre> <p>Now have a look at the console output and you will see the problem:</p> <p>Output of the first <code>System.out.println</code>, everything seems fine:</p> <pre><code>Added sequence: com.bviproject.gtfsobjects.StopSequence@d48dbbe6 Added sequence: com.bviproject.gtfsobjects.StopSequence@d5e1c8a1 Added sequence: com.bviproject.gtfsobjects.StopSequence@c98eb21 Added sequence: com.bviproject.gtfsobjects.StopSequence@79baf504 Added sequence: com.bviproject.gtfsobjects.StopSequence@6617f5f6 Added sequence: com.bviproject.gtfsobjects.StopSequence@7d7554ff </code></pre> <p>Output of the second <code>System.out.println</code>, my <code>Set</code> only contains the same object. What is happening??</p> <pre><code>com.bviproject.gtfsobjects.StopSequence@dd017ba7 com.bviproject.gtfsobjects.StopSequence@dd017ba7 com.bviproject.gtfsobjects.StopSequence@dd017ba7 com.bviproject.gtfsobjects.StopSequence@dd017ba7 com.bviproject.gtfsobjects.StopSequence@dd017ba7 com.bviproject.gtfsobjects.StopSequence@dd017ba7 com.bviproject.gtfsobjects.StopSequence@dd017ba7 com.bviproject.gtfsobjects.StopSequence@dd017ba7 </code></pre>
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USchopchop
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. COAre you certain that the code given here produces the output you gave? I ask because "Added sequence:" should be on its own line each time. Also, the code only creates *one* `StopSequence` object, so I don't see how it can even produce the first set of output. I suggest that you write a program, separate from your original code, which compiles and reproduces the exact problem which you are asking about. Make sure you restrict this new program to the code which is necessary in reproduce the issue at hand.
      singulars
      1. POSet of custom objects contains the same object
      1. USCode-Apprentice
    2. COYes I just trimmed the `\n` to save some space. I'll try to create a new StopSequence every time see if that work. But why do I get this output anyways?
      singulars
      1. POSet of custom objects contains the same object
      1. USchopchop
    3. COYep that worked, I'm still curious about why I got that output in the first place...
      singulars
      1. POSet of custom objects contains the same object
      1. USchopchop
 

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