Get a whole bunch of fun errors:
[javac] 26. public class DirectoryLister {
[javac] ^-------------^
[javac] *** Semantic Error: The return type of method
"java.lang.Appendable append(java.lang.CharSequence
$1) throws java.io.IOException;" does not match the
return type of the accessible method
"java.lang.AbstractStringBuilder
append(java.lang.CharSequence $1);" declared in type
"java.lang.AbstractStringBuilder".
[javac] 26. public class DirectoryLister {
[javac] ^-------------^
[javac] *** Semantic Error: The checked exception
"IOException" is not assignable to any exception in the
throws clause of the accessible method
"java.lang.AbstractStringBuilder
append(java.lang.CharSequence $1);" declared in type
"java.lang.AbstractStringBuilder".
[javac] 26. public class DirectoryLister {
[javac] ^-------------^
[javac] *** Semantic Error: The return type of method
"java.lang.Appendable append(char $1) throws
java.io.IOException;" does not match the return type of
the accessible method "java.lang.AbstractStringBuilder
append(char $1);" declared in type
"java.lang.AbstractStringBuilder".
[javac] 26. public class DirectoryLister {
[javac] ^-------------^
[javac] *** Semantic Error: The checked exception
"IOException" is not assignable to any exception in the
throws clause of the accessible method
"java.lang.AbstractStringBuilder append(char $1);"
declared in type "java.lang.AbstractStringBuilder".
[javac] 97. StringBuffer output = new
StringBuffer();
[javac] ^----------^
[javac] *** Semantic Error: A candidate for type
"StringBuffer" was found, but it is invalid and needs to be
fixed before this type will successfully compile.
[javac] Found 1 semantic error compiling
"/home/rob/devel/gopher/aftershock/src/aftershock/log/LogFormatter.java":
[javac] 72. StringBuffer stack = new
StringBuffer(200); // guess
[javac] ^----------^
[javac] *** Semantic Error: A candidate for type
"StringBuffer" was found, but it is invalid and needs to be
fixed before this type will successfully compile.