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POJava Reflection constructors orders
 

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  1. POJava Reflection constructors orders
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    <p>Does the order of class constructs return different results in reflection?</p> <p>I have a problem using reflection. Here is an example:</p> <pre><code>public class A{ public A() { do something here } public A(int i) { do something here } } </code></pre> <p>Then, in another class, I use reflection to get the constructors with getConstructors() method. But here is the problem. It returns only the constructor with parameters.</p> <p>So I modified the code and changed the order of constructos as:</p> <pre><code>public class A{ public A(int i) { do something here } public A() { do something here } } </code></pre> <p>Then, it returns two constructors correctly. </p> <p>Another interesting point is OpenJDK works fine with two examples, but Sun JDK does not. And I have many classes like this, SunJDK works fine in some of them, and wrong in others. Very strange.</p> <p>Any reason?</p> <p>Edit: It is a big project, here is some code for the reflection</p> <pre><code>Constructor&lt;?&gt;[] constructors = handlerClass.getDeclaredConstructors(); for (Constructor&lt;?&gt; constructor : constructors) { Class&lt;?&gt;[] parameterTypes = constructor.getParameterTypes(); </code></pre> <p>System.out.println("- " + constructor.toString()); </p> <pre><code> if (nonConnection == true &amp;&amp; parameterTypes.length == 0) { return constructor; } else if (parameterTypes.length &gt; 1) { continue; } else if (parameterTypes.length == 1) { Class&lt;?&gt; parameterType = parameterTypes[0]; if (TableManipulator.class.isAssignableFrom(parameterType)) { return constructor; } } } </code></pre> <p>handlerClass is the class to get constructors from.</p> <p>ps. I had a look at the bytecode, the bytecodes are the same except the order of the constructors.</p> <p>edit: I added a System.out to display the constructors after getParameterTypes(). It shows only one constructor.... with the old ordering, but two constructors with the new ordering.</p>
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    1. USHelic
    1. USHelic
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    1. COPlease provide the code you are using to get the constructors via reflection.
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      1. POJava Reflection constructors orders
      1. USJens Schauder
    2. COAre you sure? `getConstructors` should return *all* of a class's constructors. `getDeclaredConstructors` does something different. I'd be pretty surprised if either exhibited non-deterministic behavior.
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      1. POJava Reflection constructors orders
      1. USDave Newton
    3. COI just tested, it works as you expect with sun jdk 1.6.0_20.
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      1. USdacwe
 

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