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  1. PO
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    <p>Take a look at the <a href="http://docs.oracle.com/javase/7/docs/api/java/util/Comparator.html" rel="nofollow">java.util.Comprator</a> interface. You can write a method that iterates over a List and uses a comparator to find the one you are after.</p> <p>Something like (not compiled):</p> <pre><code>for(final T value : list) { if(comparator.compare(value, desired) == 0) { // match } } </code></pre> <p>In your comparator you have it perform whatever comparison you want.</p> <p>Here is a working example:</p> <pre><code>public class JavaApplication4 { public static void main(String[] args) { final List&lt;Data&gt; list; final List&lt;Data&gt; a; final List&lt;Data&gt; b; list = new ArrayList&lt;Data&gt;(); list.add(new Data("Foo", 1)); list.add(new Data("Bar", 10)); list.add(new Data("Car", 10)); a = find(list, new Data("Bar", 0), new Comparator&lt;Data&gt;() { @Override public int compare(final Data o1, final Data o2) { return (o1.name.compareTo(o2.name)); } }); b = find(list, new Data(null, 10), new Comparator&lt;Data&gt;() { @Override public int compare(final Data o1, final Data o2) { return (o1.count - o2.count); } }); System.out.println(a.size()); System.out.println(b.size()); } private static List&lt;Data&gt; find(final List&lt;Data&gt; list, final Data desired, final Comparator&lt;Data&gt; comprator) { final List&lt;Data&gt; results; results = new ArrayList(list.size()); for(final Data data : list) { if(comprator.compare(desired, data) == 0) { results.add(data); } } return (results); } private static class Data { private final String name; private final int count; Data(final String nm, final int c) { name = nm; count = c; } } } </code></pre> <p>And here is a generic version of the <code>find</code> method. Using this method you would never have to write the find method again, using a method that embeds the logic for matching in the iteration code means that you would have to re-write the iteration logic for each new set of matching logic.</p> <pre><code>private static &lt;T&gt; List&lt;T&gt; find(final List&lt;T&gt; list, final T desired, final Comparator&lt;T&gt; comprator) { final List&lt;T&gt; results; results = new ArrayList(list.size()); for(final T value : list) { if(comprator.compare(desired, value) == 0) { results.add(value); } } return (results); } </code></pre>
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    1. POIn java, is there a way to search for a specific field of a class stored in a linked list?
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      1. PTQuestion
    1. PTAnswer
    1. USTofuBeer
    1. USTofuBeer
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    1. This table or related slice is empty.
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    1. VO
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      1. VTUpMod
    1. COOnly thing I can think of that will do what he wants is OGNL :-P And I think it's a safe bet he don't want to go that far!!
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      1. USThihara
    2. CO@Thihara - What's wrong with iterating over the list and comparing a given value to a specific field in each element??
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      1. USjahroy
    3. COIt is flexible. It will work for the original question, and much more
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      1. USTofuBeer
 

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