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POPriorityQueue retrieve elements sorted
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  1. POPriorityQueue retrieve elements sorted
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    copied!<p>I'd like to have a sorted collection in java that I can iterate over it. From what I read a PriorityQueue is the thing that I need but hen I can't figure out how to retrieve the elements ins a sorted manner...</p> <p>I did this test example:</p> <p>Main.java</p> <pre><code>import java.util.PriorityQueue; public class Main { public static void main(String[] args) { PriorityQueue&lt;Object&gt; queue=new PriorityQueue&lt;Object&gt;(); Object o1=new Class1("o1"); Object o2=new Class2("o2"); Object o3=new Class1("o3"); Object o4=new Class1("o4"); Object o5=new Class2("o5"); Object o6=new Class2("o6"); Object o7=new Class1("o7"); Object o8=new Class2("o8"); Object o9=new Class1("o9"); Object o0=new Class1("o0"); queue.add(o7); queue.add(o4); queue.add(o3); queue.add(o8); queue.add(o5); queue.add(o1); queue.add(o2); queue.add(o9); queue.add(o0); queue.add(o6); for (Object object : queue) { System.out.println(object); } } } </code></pre> <p>Class1.java:</p> <pre><code>public class Class1 implements Comparable&lt;Object&gt;{ String name; public Class1(String name) { super(); this.name = name; } @Override public String toString() { return "Class1 [name=" + name + "]"; } @Override public int compareTo(Object o) { return (o instanceof Class1)?compareTo((Class1)o):compareTo((Class2)o); } public int compareTo(Class1 o){ return name.compareTo(o.name); } public int compareTo(Class2 o){ return name.compareTo(o.name2); } } </code></pre> <p>Class2.java:</p> <pre><code>public class Class2 implements Comparable&lt;Object&gt;{ String name2; public Class2(String name) { super(); this.name2 = name; } @Override public String toString() { return "Class2 [name=" + name2 + "]"; } @Override public int compareTo(Object o) { return (o instanceof Class1)?compareTo((Class1)o):compareTo((Class2)o); } public int compareTo(Class1 o){ return name2.compareTo(o.name); } public int compareTo(Class2 o){ return name2.compareTo(o.name2); } } </code></pre> <p>This returns:</p> <pre><code>Class1 [name=o0] Class1 [name=o1] Class2 [name=o2] Class2 [name=o5] Class2 [name=o6] Class1 [name=o4] Class1 [name=o3] Class1 [name=o9] Class2 [name=o8] Class1 [name=o7] </code></pre> <p>What do I need to do to iterate in a sorted fashion over this collection?</p>
 

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