Description Nathan Beyer 2006-02-19 18:23:17 EST

I'm not sure if this is an issue with the JDT compiler or the UI.

I have a Java class that implements an interface and a method on that interface. The method signature is modified such that the return type is the type of the class rather than the type of the interface.

When the project is configured with Java 1.4 compliance (Java 1.4 .class files, Java 1.4 source), the methods are marked with errors that say: "The return type is incompatible with Appendable.append(char)". When the project is configured with Java 5.0 compliance (Java 1.4 .class files, Java 1.4 source), the class compiles fine. In both cases, the JRE libraries are from a Java 5 distribution (I've used both a Sun JRE and a BEA JRE).

My assumption is that since I'm setting the ".class file compliance" and "source file compliance" to "1.4", they should work the same.

I've tested this in 3.1.2, 3.2M4 and 3.2M5 and they all report the same results.

I looked for related bugs and I think this may be related to bug 105808, bug 81535 and bug 58715.

Example:
public class StringAppender implements Appendable {
    public StringAppender append(char c) {
        return null;
    }
    //snip
}

public interface Appendable { //from java.lang
    public Appendable append(char c);
    //snip
}