1 files changed, 41 insertions, 0 deletions
diff --git a/ri/src/main/java/javax/annotation/Nonnegative.java b/ri/src/main/java/javax/annotation/Nonnegative.java
new file mode 100644
index 0000000..21d1793
--- /dev/null
+++ b/ri/src/main/java/javax/annotation/Nonnegative.java
@@ -0,0 +1,41 @@
+package javax.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import javax.annotation.meta.TypeQualifier;
+import javax.annotation.meta.TypeQualifierValidator;
+import javax.annotation.meta.When;
+
+/** Used to annotate a value that should only contain nonnegative values */
+@Documented
+@TypeQualifier(applicableTo = Number.class)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface Nonnegative {
+    When when() default When.ALWAYS;
+
+    class Checker implements TypeQualifierValidator<Nonnegative> {
+
+        public When forConstantValue(Nonnegative annotation, Object v) {
+            if (!(v instanceof Number))
+                return When.NEVER;
+            boolean isNegative;
+            Number value = (Number) v;
+            if (value instanceof Long)
+                isNegative = value.longValue() < 0;
+            else if (value instanceof Double)
+                isNegative = value.doubleValue() < 0;
+            else if (value instanceof Float)
+                isNegative = value.floatValue() < 0;
+            else
+                isNegative = value.intValue() < 0;
+
+            if (isNegative)
+                return When.NEVER;
+            else
+                return When.ALWAYS;
+
+        }
+    }
+}