I am using the @Retention and @StringDef annotations for some of my methods in a library and I face a strange warning, I want to understand.
In a static class, SIP, I use this annotation:
public static final String CODEC_SPEEX_16K = "speex/16000/1";
public static final String CODEC_SPEEX_8K = "speex/8000/1";
public static final String CODEC_SPEEX_32K = "speex/32000/1";
public static final String CODEC_ILBC_8K = "iLBC/8000/1";
public static final String CODEC_GSM_8K = "GSM/8000/1";
public static final String CODEC_PCMU_8K = "PCMU/8000/1";
public static final String CODEC_PCMA_8K = "PCMA/8000/1";
public static final String CODEC_G722_16K = "G722/16000/1";
@Retention(RetentionPolicy.CLASS)
@StringDef({
CODEC_SPEEX_16K,
CODEC_SPEEX_8K,
CODEC_SPEEX_32K,
CODEC_ILBC_8K,
CODEC_GSM_8K,
CODEC_PCMU_8K,
CODEC_PCMA_8K,
CODEC_G722_16K
})
public @interface CodecName {}
which compiles fine, without any warnings.
In the static class Tools I use this annotation:
public static final String RES_TYPE_STRING = "string";
public static final String RES_TYPE_DRAWABLE = "drawable";
public static final String RES_TYPE_LAYOUT = "layout";
public static final String RES_TYPE_VIEW = "id";
public static final String RES_TYPE_DIMEN = "dimen";
public static final String RES_TYPE_COLOR = "color";
public static final String RES_TYPE_ANIM = "anim";
public static final String RES_TYPE_MIPMAP = "mipmap";
@Retention(RetentionPolicy.CLASS)
@StringDef({
RES_TYPE_STRING,
RES_TYPE_DRAWABLE,
RES_TYPE_LAYOUT,
RES_TYPE_DIMEN,
RES_TYPE_COLOR,
RES_TYPE_ANIM,
RES_TYPE_VIEW,
RES_TYPE_MIPMAP
})
public @interface ResourceType {
}
and I get the warning:
The typedef annotation ....toolbox.Tools.ResourceType should have @Retention(RetentionPolicy.SOURCE)
It seems to be uncritical, everything works fine. But can someone please explain me, why
Annotation#1 does not get a warning ;
Annotation#2 gets a warning;
Both are built identical, both only used in static context. From my point of view, both are the same.