deyou
39 lines
835 B
Java
39 lines
835 B
Java
package verifier;
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import java.applet.*;
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import java.awt.*;
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/**
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* This application demonstrates the bytecode verifier of the virtual machine. If you use a hex
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* editor to modify the class file, then the virtual machine should detect the tampering.
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* @version 1.00 1997-09-10
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* @author Cay Horstmann
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*/
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public class VerifierTest extends Applet
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{
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public static void main(String[] args)
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{
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System.out.println("1 + 2 == " + fun());
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}
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/**
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* A function that computes 1 + 2.
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* @return 3, if the code has not been corrupted
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*/
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public static int fun()
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{
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int m;
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int n;
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m = 1;
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n = 2;
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// use hex editor to change to "m = 2" in class file
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int r = m + n;
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return r;
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}
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public void paint(Graphics g)
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{
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g.drawString("1 + 2 == " + fun(), 20, 20);
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}
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}
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