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draw a triangle

 
Iain Palmer
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i am writing a program that ask you to think of a shape then ask how many sides it has got, then I would like to draw the shape be it a circle, traingle, square/rectangle. I can draw a circle and square/rectangle, but am having difficulty draw a traingle. I am using the polygon class in the awt package
here is a sample bit of a test program.



When I compile it I get the followig error
C:\Documents and Settings\Iain Palmer\Java2dGraphics\src\java2dgraphics\TriangleTest.java:23:
illegal start of expression
private Shape = new Polygon(int [0,50,0] xPoints,int[0,50,0] yPoints);
1 error
 
Jeff Albertson
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Let me suggest that your syntax error isn't about triangles or polygons per se, but about how to create an array, initialize it and pass it as an argument to a constructor or method. Here are three ways to do that.

In the first version, I create, intialize and passing the arrays in separate stages. This is death by tedium here, but necessary if the intializiation is more complex, say if it involved a loop:

In the second version I use the special syntax of an array initializer to provide initial values.

In the third and tersest example, I create, initialize and pass the arrays all together. If you are uncomfortable with this shortest version, stick to the second one.

Now in your code, you wrote there are several mistakes:

1. when you invoke a method or constructor, don't repeat the argument type (int) or the arguments
formal parameter name (xPoints, yPoints). I also think you confused array notation -- [] -- with the array initializer -- {0, 50, 0}.
 
Iain Palmer
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Brillliant thank you it was just the problem with the initialization
 
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