48 lines
1.5 KiB
Java
48 lines
1.5 KiB
Java
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NegativeLength Exception
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import java.io.*;
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public class NegativeLengthException extends Exception {
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/** Test NegativeLengthException */
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public static void main(String[] args) {
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try {
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int lineLength = readLength();
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for(int i=0; i System.out.print("*");
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}
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System.out.println();
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} catch (NegativeLengthException nle) {
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System.out.println("NegativeLengthException: " +
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nle.getMessage());
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}
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}
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public NegativeLengthException() {
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super("Negative dimensions not permitted.");
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}
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public NegativeLengthException(String message) {
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super(message);
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}
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// readLength catches IOExceptions locally but lets the
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// calling method handle NegativeLengthExceptions.
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private static int readLength() throws NegativeLengthException {
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BufferedReader in = new BufferedReader(
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new InputStreamReader(System.in));
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System.out.print("Enter length: ");
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System.out.flush();
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int len = 0;
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try {
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String line = in.readLine();
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len = Integer.parseInt(line);
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if (len < 0) {
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throw new NegativeLengthException();
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}
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} catch (IOException ioe) {
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System.out.println("Problem reading from keyboard");
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}
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return(len);
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}
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}
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