Add util methods to validate satellite config data

isValidPattern
isValidCountryCode

Bug: 332963485
Test: atest com.android.internal.telephony.tests

Change-Id: I6ebfdadc4a51f34d1eb4976176f8343c53791cff

telephony/common/com/android/internal/telephony/util/TelephonyUtils.java

@@ -349,21 +349,38 @@ public final class TelephonyUtils {
     }
 
     /**
-     * @param plmn target plmn for validation.
-     * @return {@code true} if the target plmn is valid {@code false} otherwise.
+     * @param input string that want to be compared.
+     * @param regex string that express regular expression
+     * @return {@code true} if matched  {@code false} otherwise.
      */
-    public static boolean isValidPlmn(@Nullable String plmn) {
-        if (TextUtils.isEmpty(plmn)) {
+    private static boolean isValidPattern(@Nullable String input, @Nullable String regex) {
+        if (TextUtils.isEmpty(input) || TextUtils.isEmpty(regex)) {
             return false;
         }
-        Pattern pattern = Pattern.compile("^(?:[0-9]{3})(?:[0-9]{2}|[0-9]{3})$");
-        Matcher matcher = pattern.matcher(plmn);
+        Pattern pattern = Pattern.compile(regex);
+        Matcher matcher = pattern.matcher(input);
         if (!matcher.matches()) {
             return false;
         }
         return true;
     }
 
+    /**
+     * @param countryCode two letters country code based on the ISO 3166-1.
+     * @return {@code true} if the countryCode is valid {@code false} otherwise.
+     */
+    public static boolean isValidCountryCode(@Nullable String countryCode) {
+        return isValidPattern(countryCode, "^[A-Za-z]{2}$");
+    }
+
+    /**
+     * @param plmn target plmn for validation.
+     * @return {@code true} if the target plmn is valid {@code false} otherwise.
+     */
+    public static boolean isValidPlmn(@Nullable String plmn) {
+        return isValidPattern(plmn, "^(?:[0-9]{3})(?:[0-9]{2}|[0-9]{3})$");
+    }
+
     /**
      * @param serviceType target serviceType for validation.
      * @return {@code true} if the target serviceType is valid {@code false} otherwise.

tests/TelephonyCommonTests/src/com/android/internal/telephony/tests/TelephonyUtilsTest.java

@@ -85,6 +85,8 @@ public class TelephonyUtilsTest {
         assertTrue(TelephonyUtils.isValidPlmn("45006"));
         assertFalse(TelephonyUtils.isValidPlmn("1234567"));
         assertFalse(TelephonyUtils.isValidPlmn("1234"));
+        assertFalse(TelephonyUtils.isValidPlmn(""));
+        assertFalse(TelephonyUtils.isValidPlmn(null));
     }
 
     @Test
@@ -94,6 +96,19 @@ public class TelephonyUtilsTest {
         assertFalse(TelephonyUtils.isValidService(FIRST_SERVICE_TYPE - 1));
         assertFalse(TelephonyUtils.isValidService(LAST_SERVICE_TYPE + 1));
     }
+
+    @Test
+    public void testIsValidCountryCode() {
+        assertTrue(TelephonyUtils.isValidCountryCode("US"));
+        assertTrue(TelephonyUtils.isValidCountryCode("cn"));
+        assertFalse(TelephonyUtils.isValidCountryCode("11"));
+        assertFalse(TelephonyUtils.isValidCountryCode("USA"));
+        assertFalse(TelephonyUtils.isValidCountryCode("chn"));
+        assertFalse(TelephonyUtils.isValidCountryCode("U"));
+        assertFalse(TelephonyUtils.isValidCountryCode("G7"));
+        assertFalse(TelephonyUtils.isValidCountryCode(""));
+        assertFalse(TelephonyUtils.isValidCountryCode(null));
+    }
 }