javac reports throws clause errors in a code that has none.

allan.jacobs@Eng 1996-12-18


algol% cat c0846442.java
/**
 ** JAVATEST : The Modena JAVA Test Suite, Version 2.0, November 1996
 ** Copyright (c) 1996 Modena Software (I) Pvt. Ltd., All Rights Reserved
 **/

/*
 * Section: 8.4.6.4
 *
 * Filename: c0846442.java
 *
 * Purpose: Positive test for section 8.4.6.4, para 1:
 *
 * "A compile-time error occurs if, for any two such inherited
 * methods, either they have different return types or one
 * has a return type and the other is void. (The throws
 * clauses do not cause errors in this case)."
 *
 * Language Specification: October, 1996
 */

import java.io.*;

interface I1 {
  int f() throws RuntimeException;
}
interface I2 {
  int f() throws IOException;
}

abstract class Y implements I2,I1 {}
// Note the order of implementation of I1 & I2

class X {
   public static void main(String[] arg)
    {
      System.out.println("Done");
    }
}
algol% ls
c0846442.java c0846442.java.orig
algol% setenv CLASSPATH .
algol% javac -d . c0846442.java
c0846442.java:27: Invalid exception class java.io.IOException in throws clause. The exception must be a subclass of an exception thrown by int f() from interface I1.
  int f() throws IOException;
      ^
1 error
algol% ls
I1.class X.class c0846442.java.orig
I2.class c0846442.java
algol% java X
Done
algol% echo $status
0