AccountSshKey.Id: Add isValid() method

The isValid() method returns false when the Id's sequence number is
invalid (i.e. < 1).

Extend AccountSshKey#isValid() to also check its Id's validity.

Change-Id: I7b428b06cc5bbb04cceef20d9f284e58071b9abe
diff --git a/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/AccountSshKey.java b/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/AccountSshKey.java
index 7b1e874..a28fc60 100644
--- a/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/AccountSshKey.java
+++ b/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/AccountSshKey.java
@@ -53,6 +53,10 @@
     protected void set(int newValue) {
       seq = newValue;
     }
+
+    public boolean isValid() {
+      return seq > 0;
+    }
   }
 
   @Column(id = 1, name = Column.NONE)
@@ -70,7 +74,7 @@
   public AccountSshKey(final AccountSshKey.Id i, final String pub) {
     id = i;
     sshPublicKey = pub;
-    valid = true; // We can assume it is fine.
+    valid = id.isValid();
   }
 
   public Account.Id getAccount() {
@@ -125,7 +129,7 @@
   }
 
   public boolean isValid() {
-    return valid;
+    return valid && id.isValid();
   }
 
   public void setInvalid() {
diff --git a/gerrit-reviewdb/src/test/java/com/google/gerrit/reviewdb/client/AccountSshKeyTest.java b/gerrit-reviewdb/src/test/java/com/google/gerrit/reviewdb/client/AccountSshKeyTest.java
new file mode 100644
index 0000000..06d5b90
--- /dev/null
+++ b/gerrit-reviewdb/src/test/java/com/google/gerrit/reviewdb/client/AccountSshKeyTest.java
@@ -0,0 +1,39 @@
+// Copyright (C) 2016 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.reviewdb.client;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import org.junit.Test;
+
+public class AccountSshKeyTest {
+  private static final String KEY =
+      "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAgQCgug5VyMXQGnem2H1KVC4/HcRcD4zzBqS"
+      + "uJBRWVonSSoz3RoAZ7bWXCVVGwchtXwUURD689wFYdiPecOrWOUgeeyRq754YWRhU+W28"
+      + "vf8IZixgjCmiBhaL2gt3wff6pP+NXJpTSA4aeWE5DfNK5tZlxlSxqkKOS8JRSUeNQov5T"
+      + "w== john.doe@example.com";
+
+  @Test
+  public void testValidity() throws Exception {
+    Account.Id accountId = new Account.Id(1);
+    AccountSshKey key = new AccountSshKey(
+        new AccountSshKey.Id(accountId, -1), KEY);
+    assertThat(key.isValid()).isFalse();
+    key = new AccountSshKey(new AccountSshKey.Id(accountId, 0), KEY);
+    assertThat(key.isValid()).isFalse();
+    key = new AccountSshKey(new AccountSshKey.Id(accountId, 1), KEY);
+    assertThat(key.isValid()).isTrue();
+  }
+}