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POHow to get the parameter names of an object's constructors (reflection)?
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copied!<p>Say I somehow got an object reference from an other class:</p> <pre><code>Object myObj = anObject; </code></pre> <p>Now I can get the class of this object:</p> <pre><code>Class objClass = myObj.getClass(); </code></pre> <p>Now, I can get all constructors of this class:</p> <pre><code>Constructor[] constructors = objClass.getConstructors(); </code></pre> <p>Now, I can loop every constructor:</p> <pre><code>if (constructors.length > 0) { for (int i = 0; i < constructors.length; i++) { System.out.println(constructors[i]); } } </code></pre> <p>This is already giving me a good summary of the constructor, for example a constructor public Test(String paramName) is shown as public Test(java.lang.String)</p> <p>Instead of giving me the class type however, I want to get the name of the parameter.. in this case "paramName". How would I do that? I tried the following without success:</p> <pre><code>if (constructors.length > 0) { for (int iCon = 0; iCon < constructors.length; iCon++) { Class[] params = constructors[iCon].getParameterTypes(); if (params.length > 0) { for (int iPar = 0; iPar < params.length; iPar++) { Field fields[] = params[iPar].getDeclaredFields(); for (int iFields = 0; iFields < fields.length; iFields++) { String fieldName = fields[i].getName(); System.out.println(fieldName); } } } } } </code></pre> <p>Unfortunately, this is not giving me the expected result. Could anyone tell me how I should do this or what I am doing wrong? Thanks!</p>

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