问如何阻止Proguard删除返回类型？

EN

# Keep the annotation.
-keep @interface org.mozilla.gecko.mozglue.JNITarget

# Keep classes tagged with the annotation.
-keep @org.mozilla.gecko.mozglue.JNITarget class *

# Keep all members of an annotated class.
-keepclassmembers @org.mozilla.gecko.mozglue.JNITarget class * {
    *;
}

# Keep annotated members of any class.
-keepclassmembers class * {
    @org.mozilla.gecko.mozglue.JNITarget *;
}

# Keep classes which contain at least one annotated element. Split over two directives
# because, according to the developer of ProGuard, "the option -keepclasseswithmembers
# doesn't combine well with the '*' wildcard" (And, indeed, using it causes things to
# be deleted that we want to keep.)
-keepclasseswithmembers class * {
    @org.mozilla.gecko.mozglue.JNITarget <methods>;
}
-keepclasseswithmembers class * {
    @org.mozilla.gecko.mozglue.JNITarget <fields>;
}

 public org.mozilla.gecko.Tab loadUrl(java.lang.String);

 public mt loadUrl(java.lang.String);