Invoke a constructor which throws Exception : Constructor « Reflection « Java Tutorial






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import static java.lang.System.err;

import java.lang.reflect.InvocationTargetException;

public class ConstructorTroubleToo {
  public ConstructorTroubleToo() {
    throw new RuntimeException("exception in constructor");
  }

  public static void main(String... args) {
    try {
      Class<?> c = Class.forName("ConstructorTroubleToo");
      // Method propagetes any exception thrown by the constructor (including checked exceptions).
      if (args.length > 0 && args[0].equals("class")) {
        Object o = c.newInstance();
      } else {
        Object o = c.getConstructor().newInstance();
      }

      // production code should handle these exceptions more gracefully
    } catch (ClassNotFoundException x) {
      x.printStackTrace();
    } catch (InstantiationException x) {
      x.printStackTrace();
    } catch (IllegalAccessException x) {
      x.printStackTrace();
    } catch (NoSuchMethodException x) {
      x.printStackTrace();
    } catch (InvocationTargetException x) {
      x.printStackTrace();
      err.format("%n%nCaught exception: %s%n", x.getCause());
    }
  }
}








7.3.Constructor
7.3.1.Get all constructors or by parameters
7.3.2.Demonstrates use of Constructor objects
7.3.3.A program that displays a class synopsis for the named class
7.3.4.Create new instance from Constructor
7.3.5.Modifier.PUBLIC | Modifier.PRIVATE | Modifier.PROTECTED
7.3.6.Load class with Class.forName
7.3.7.Call Private constructor
7.3.8.Get constructor by parameter type
7.3.9.Invoke a constructor which throws Exception
7.3.10.Passing a parameter to the constructor and calling a method dynamically
7.3.11.Getting a Constructor of a Class Object: By obtaining a list of all Constructors object
7.3.12.Getting a Constructor of a Class Object: By obtaining a particular Constructor object.
7.3.13.Get a compatible constructor for the given value type
7.3.14.Has Declared Constructor