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POWhy is this coming up with missing main method error?
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copied!<p>So this source code comes free from this website. <a href="http://math.hws.edu/javamath/basic_applets/SliderGraph.html" rel="nofollow">http://math.hws.edu/javamath/basic_applets/SliderGraph.html</a> It seems to be somewhat old but I don't know if that is the issue. I would really like to write my own applet but this is exactly what I need and I am very short on time. The code compiles fine with no errors but comes up Exception in thread main java.lang.NoSuchMethodError: main Why is this happening? Where should I add the main method?</p> <pre><code>import java.awt.*; import edu.hws.jcm.data.*; import edu.hws.jcm.draw.*; import edu.hws.jcm.awt.*; public class SliderGraph extends java.applet.Applet { private DisplayCanvas canvas; public void stop() { canvas.releaseResources(); } JCMPanel makeSliderPanel(VariableSlider v) { // A small utility routing that makes a JCMPanel that contains // a VariableSlider and a DisplayLabel that shows the value // of the variable associated with that slider. JCMPanel p = new JCMPanel(); p.add(v, BorderLayout.CENTER); p.add( new DisplayLabel(v.getName() + " = #", new Value[] { v } ), BorderLayout.EAST); return p; } public void init() { Parser parser = new Parser(); Variable x = new Variable("x"); parser.add(x); // Create the three VariableSliders. In this case, the sliders have // names. There is also a Variable associated with each slider, // which has the same name. This variable is added to the parser // which is passed as the fourth parameter to the constructor, making // it possible to use "a", "b", and "c" in expressions parsed by the // parser. Adjusting the value on a slider changes the value of the // associated variable, and therefore changes the value of any // expression that refers to that variable. The second and third // parameters to the constructor give the minimum and maximum Values // on the slider. Passing "null,null" uses the defaults, namely // new Constant(-5) and new Constant(5). VariableSlider a = new VariableSlider("a",null,null,parser); VariableSlider b = new VariableSlider("b",null,null,parser); VariableSlider c = new VariableSlider("c",null,null,parser); canvas = new DisplayCanvas(); canvas.setHandleMouseZooms(true); canvas.add(new Panner()); LimitControlPanel limits = new LimitControlPanel( LimitControlPanel.SET_LIMITS | LimitControlPanel.RESTORE | LimitControlPanel.EQUALIZE, false); limits.addCoords(canvas); ExpressionInput input = new ExpressionInput("a*x^2 + b*x + c", parser); Graph1D graph = new Graph1D(input.getFunction(x)); ComputeButton button = new ComputeButton("Graph it!"); canvas.add(new Axes()); canvas.add(graph); canvas.add(new DrawBorder(Color.darkGray, 2)); JCMPanel main = new JCMPanel(); // Build interface out of JCMPanels! main.setInsetGap(3); main.add(canvas, BorderLayout.CENTER); main.add(limits, BorderLayout.EAST); JCMPanel bot = new JCMPanel(5,1); main.add(bot, BorderLayout.SOUTH); bot.add(new Label("Enter a function f(x), which can use the constants a, b, and c:")); JCMPanel inputPanel = new JCMPanel(); bot.add(inputPanel); inputPanel.add(input, BorderLayout.CENTER); inputPanel.add(button, BorderLayout.EAST); bot.add( makeSliderPanel(a) ); // Create and add the sliders. bot.add( makeSliderPanel(b) ); bot.add( makeSliderPanel(c) ); Controller controller = main.getController(); // Set up error reporting. controller.setErrorReporter(canvas); limits.setErrorReporter(canvas); main.gatherInputs(); // Set up main panel to respond to changes in input objects. // This works since the interface is built of JCMPanels. For // the same reason, I don't have to add the objects the the // controller. button.setOnUserAction(controller); // Set controller to respond to button. setBackground(Color.lightGray); setLayout(new BorderLayout()); add(main,BorderLayout.CENTER); } // end init() } // end class SliderGraph </code></pre>

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