Annotation information missed after compiled with ECJ Compiler - eclipse

Question

I found the bytecode compiled from ECJ compiler has the annotation information missing.
The source code decompiled from bytecode compiled by javac:
public class HelloWorldApp {
#GetAction("/hello")
public String sayHello() {
return "Hello World!";
}
}
The source code decompiled from bytecode compiled by ECJ:
public class HelloWorldApp {
public String sayHello() {
return "Hello World!";
}
}
So clearly the annotation #GetAction("/hello") is missing from the bytecode compiled by ECJ (in memory compilation).
Anyone has encountered this issue before and get any clue?
Update with more information
Take a look at the following screenshot:
So it is in the ASTNode.resolveAnnotations() methods line #797:
A) The state if ((method.tagBits & TagBits.AnnotationResolved) != 0) return annotations; will return null as annotations even
B) the source annotation #GetAction("/hello") is presented because
C) the this.annotations field is null and
D) the if condition (method.tagBits & TagBits.AnnotationResolved) != 0 evaluates to true
Updates 2
It looks like I captured the screen too early, so once process finished, I found the annotations information get stored:
However I still can't get the annotation information from the result file. Click here to download the bytecode file generated:
Note I am using ECJ 4.4.1:
<dependency>
<groupId>org.eclipse.jdt.core.compiler</groupId>
<artifactId>ecj</artifactId>
<version>4.4.1</version>
</dependency>

Answer 1

Problem solved! Just add the following lines:
opt(map, OPTION_TargetPlatform, "1.6");
The issue is caused by default JDK version is 1.2 in ECJ, which does not support annotation