Replace <code> with {@code} in javadoc

{@code foo} is shorter and easier to read and write than
<code>foo</code>, which is why it was introduced years ago in the
javadoc processor.  Make consistent use of it throughout the
documentation comments.

Change-Id: I59d428cb6c5015453629398b0697891b83c8e91d

gerrit-server/src/main/java/com/google/gerrit/server/ProjectUtil.java

@@ -29,9 +29,9 @@ public class ProjectUtil {
    *
    * @param repoManager Git repository manager to open the git repository
    * @param branch the branch for which it should be checked if it exists
-   * @return <code>true</code> if the specified branch exists or if
-   *         <code>HEAD</code> points to this branch, otherwise
-   *         <code>false</code>
+   * @return {@code true} if the specified branch exists or if
+   *         {@code HEAD} points to this branch, otherwise
+   *         {@code false}
    * @throws RepositoryNotFoundException the repository of the branch's project
    *         does not exist.
    * @throws IOException error while retrieving the branch from the repository.

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

@@ -69,13 +69,13 @@ public class PerformCreateGroup {
    * Creates a new group.
    *
    * @param groupName the name for the new group
-   * @param groupDescription the description of the new group, <code>null</code>
+   * @param groupDescription the description of the new group, {@code null}
    *        if no description
-   * @param visibleToAll <code>true</code> to make the group visible to all
-   *        registered users, if <code>false</code> the group is only visible to
+   * @param visibleToAll {@code true} to make the group visible to all
+   *        registered users, if {@code false} the group is only visible to
    *        the group owners and Gerrit administrators
    * @param ownerGroupId the group that should own the new group, if
-   *        <code>null</code> the new group will own itself
+   *        {@code null} the new group will own itself
    * @param initialMembers initial members to be added to the new group
    * @param initialGroups initial groups to include in the new group
    * @return the id of the new group

gerrit-server/src/main/java/com/google/gerrit/server/change/MergeabilityChecker.java

@@ -109,8 +109,8 @@ public class MergeabilityChecker implements GitReferenceUpdatedListener {
    *
    * @param change the change for which the mergeability flag should be updated
    * @return CheckedFuture that updates the mergeability flag of the change and
-   *         returns <code>true</code> if the mergeability flag was updated and
-   *         the change was reindexed, and <code>false</code> if the
+   *         returns {@code true} if the mergeability flag was updated and
+   *         the change was reindexed, and {@code false} if the
    *         mergeability flag was not updated and the change was not reindexed
    */
   public CheckedFuture<Boolean, IOException> updateAsync(Change change) {

gerrit-server/src/main/java/com/google/gerrit/server/git/MultiProgressMonitor.java

@@ -179,7 +179,7 @@ public class MultiProgressMonitor {
    * <p>
    * Must be called from the main thread, <em>not</em> a worker thread. Once a
    * worker thread calls {@link #end()}, the future has an additional
-   * <code>maxInterval</code> to finish before it is forcefully cancelled and
+   * {@code maxInterval} to finish before it is forcefully cancelled and
    * {@link ExecutionException} is thrown.
    *
    * @param workerFuture a future that returns when worker threads are finished.

gerrit-server/src/main/java/com/google/gerrit/server/git/NotesBranchUtil.java

@@ -88,8 +88,8 @@ public class NotesBranchUtil {
   }
 
   /**
-   * Create a new commit in the <code>notesBranch</code> by updating existing
-   * or creating new notes from the <code>notes</code> map.
+   * Create a new commit in the {@code notesBranch} by updating existing
+   * or creating new notes from the {@code notes} map.
    *
    * @param notes map of notes
    * @param notesBranch notes branch to update
@@ -106,16 +106,16 @@ public class NotesBranchUtil {
   }
 
   /**
-   * Create a new commit in the <code>notesBranch</code> by creating not yet
-   * existing notes from the <code>notes</code> map. The notes from the
-   * <code>notes</code> map which already exist in the note-tree of the
-   * tip of the <code>notesBranch</code> will not be updated.
+   * Create a new commit in the {@code notesBranch} by creating not yet
+   * existing notes from the {@code notes} map. The notes from the
+   * {@code notes} map which already exist in the note-tree of the
+   * tip of the {@code notesBranch} will not be updated.
    *
    * @param notes map of notes
    * @param notesBranch notes branch to update
    * @param commitAuthor author of the commit in the notes branch
    * @param commitMessage for the commit in the notes branch
-   * @return map with those notes from the <code>notes</code> that were newly
+   * @return map with those notes from the {@code notes} that were newly
    *         created
    * @throws IOException
    * @throws ConcurrentRefUpdateException

gerrit-server/src/main/java/com/google/gerrit/server/git/SubmitStrategy.java

@@ -125,8 +125,8 @@ public abstract class SubmitStrategy {
    * @param mergeTip the mergeTip
    * @param toMerge the commit for which it should be checked whether it can be
    *        merged or not
-   * @return <code>true</code> if the given commit can be merged, otherwise
-   *         <code>false</code>
+   * @return {@code true} if the given commit can be merged, otherwise
+   *         {@code false}
    * @throws MergeException
    */
   public abstract boolean dryRun(CodeReviewCommit mergeTip,
@@ -140,7 +140,7 @@ public abstract class SubmitStrategy {
    * Do only call this method after the {@link #run(CodeReviewCommit, List)}
    * method has been invoked.
    *
-   * @return the ref log identity, may be <code>null</code>
+   * @return the ref log identity, may be {@code null}
    */
   public final PersonIdent getRefLogIdent() {
     return refLogIdent;
@@ -168,9 +168,9 @@ public abstract class SubmitStrategy {
    *
    * May be overwritten by subclasses.
    *
-   * @return <code>true</code> if a merge that failed with
+   * @return {@code true} if a merge that failed with
    *         {@link Result#LOCK_FAILURE} should be retried, otherwise
-   *         <code>false</code>
+   *         {@code false}
    */
   public boolean retryOnLockFailure() {
     return true;

gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectNode.java

@@ -46,7 +46,7 @@ public class ProjectNode implements TreeNode, Comparable<ProjectNode> {
   /**
    * Returns the project parent name.
    *
-   * @return Project parent name, <code>null</code> for the 'All-Projects' root
+   * @return Project parent name, {@code null} for the 'All-Projects' root
    *         project
    */
   public Project.NameKey getParentName() {

gerrit-server/src/main/java/com/google/gerrit/server/project/SubmitRuleEvaluator.java

@@ -88,7 +88,7 @@ public class SubmitRuleEvaluator {
    *        rule.
    * @param filterRuleWrapperName The name of the rule used to evaluate the
    *        filter rule.
-   * @param skipSubmitFilters if <code>true</code> submit filter will not be
+   * @param skipSubmitFilters if {@code true} submit filter will not be
    *        applied
    * @param rules when non-null the rules will be read from this input stream
    *        instead of refs/meta/config:rules.pl file

gerrit-server/src/main/java/com/google/gerrit/server/schema/DataSourceType.java

@@ -28,7 +28,7 @@ public interface DataSourceType {
 
   /**
    * Return a ScriptRunner that runs the index script. Must not return
-   * <code>null</code>, but may return a ScriptRunner that does nothing.
+   * {@code null}, but may return a ScriptRunner that does nothing.
    *
    * @throws IOException
    */

gerrit-server/src/main/java/com/google/gerrit/server/util/MagicBranch.java

@@ -51,7 +51,7 @@ public final class MagicBranch {
         || refName.startsWith(NEW_CHANGE);
   }
 
-  /** Returns the ref name prefix for a magic branch, <code>null</code> if the branch is not magic */
+  /** Returns the ref name prefix for a magic branch, {@code null} if the branch is not magic */
   public static String getMagicRefNamePrefix(String refName) {
     if (refName.startsWith(NEW_DRAFT_CHANGE)) {
       return NEW_DRAFT_CHANGE;