Rewrite our build as modular maven components

This refactoring splits the code up into different components, with
their own per-component CLASSPATH.  By moving all of our classes
into isolated components we can better isolate the classpaths and
try to avoid unexpected dependency problems.  It also allows us to
more clearly define which components are used by the GWT UI and
thus must be compiled under GWT, and which components are run on
the server and can therefore use more of the J2SE API.

Change-Id: I833cc22bacc5655d1c9099ed7c2b0e0a5b08855a
Signed-off-by: Shawn O. Pearce <sop@google.com>

gerrit-server/src/main/java/com/google/gerrit/server/account/AccountResolver.java

@@ -0,0 +1,86 @@
+// Copyright (C) 2009 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.server.account;
+
+import com.google.gerrit.reviewdb.Account;
+import com.google.gerrit.reviewdb.ReviewDb;
+import com.google.gwtorm.client.OrmException;
+import com.google.gwtorm.client.ResultSet;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+
+import java.util.List;
+import java.util.Set;
+
+public class AccountResolver {
+  private final Realm realm;
+  private final AccountByEmailCache byEmail;
+  private final AccountCache byId;
+  private final Provider<ReviewDb> schema;
+
+  @Inject
+  AccountResolver(final Realm realm, final AccountByEmailCache byEmail,
+      final AccountCache byId, final Provider<ReviewDb> schema) {
+    this.realm = realm;
+    this.byEmail = byEmail;
+    this.byId = byId;
+    this.schema = schema;
+  }
+
+  /**
+   * Locate exactly one account matching the name or name/email string.
+   *
+   * @param nameOrEmail a string of the format
+   *        "Full Name &lt;email@example&gt;", or just the email address
+   *        ("email@example"), or a full name, or an account id.
+   * @return the single account that matches; null if no account matches or
+   *         there are multiple candidates.
+   */
+  public Account find(final String nameOrEmail) throws OrmException {
+    if (nameOrEmail.matches("^[1-9][0-9]*$")) {
+      return byId.get(Account.Id.parse(nameOrEmail)).getAccount();
+    }
+
+    final int lt = nameOrEmail.indexOf('<');
+    final int gt = nameOrEmail.indexOf('>');
+    if (lt >= 0 && gt > lt && nameOrEmail.contains("@")) {
+      return findByEmail(nameOrEmail.substring(lt + 1, gt));
+    }
+
+    if (nameOrEmail.contains("@")) {
+      return findByEmail(nameOrEmail);
+    }
+
+    final Account.Id id = realm.lookup(nameOrEmail);
+    if (id != null) {
+      return byId.get(id).getAccount();
+    }
+
+    return oneAccount(schema.get().accounts().byFullName(nameOrEmail));
+  }
+
+  private Account findByEmail(final String email) {
+    final Set<Account.Id> candidates = byEmail.get(email);
+    if (1 == candidates.size()) {
+      return byId.get(candidates.iterator().next()).getAccount();
+    }
+    return null;
+  }
+
+  private static Account oneAccount(final ResultSet<Account> rs) {
+    final List<Account> r = rs.toList();
+    return r.size() == 1 ? r.get(0) : null;
+  }
+}