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The following statement produces a compilation error in JDT, even though it looks to me as a syntactically correct statement: char a = '\u000a'; same result is obtained for char a = '\u000A'; Trying to comment the line out by appending the line with // still produces a compile-time error, which clearly indicates that something is wrong. ---- Other unicode character sequences such as char a = '\u000b'; are accepted as correct.
\u000a is a line break and this is illegal inside a character constant. We report: 1. ERROR in C:\tests_sources\X.java (at line 2) char a = '\u000a'; ^^^^^^^ Invalid character constant javac 1.4.2 reports: C:\tests_sources>javac X.java X.java:2: illegal line end in character literal char a = '\u000a'; ^ 1 error jikes 1.18 reports: C:\tests_sources>jikes -classpath c:\jdks\jdk1.4.1_05\jre\lib\rt.jar X.java Found 2 lexical errors in "C:/tests_sources/X.java": 2. char a = ' ^ *** Lexical Error: Character constant not properly terminated. 3. '; ^^ *** Lexical Error: Character constant not properly terminated. Found 1 syntax error in "C:/tests_sources/X.java": 3. '; ^^ *** Syntax: ; expected instead of this token See http://java.sun.com/docs/books/jls/second_edition/html/lexical.doc.html#100964: Because Unicode escapes are processed very early, it is not correct to write '\u000a' for a character literal whose value is linefeed (LF); the Unicode escape \u000a is transformed into an actual linefeed in translation step 1 (§3.3) and the linefeed becomes a LineTerminator in step 2 (§3.4), and so the character literal is not valid in step 3. Instead, one should use the escape sequence '\n' (§3.10.6). Similarly, it is not correct to write '\u000d' for a character literal whose value is carriage return (CR). Instead, use '\r'. So this is an invalid code that is properly rejected by the Eclipse compiler. Close as INVALID.
