#1268 - SQL Server fix for "for update" plus Sequences support plus refactor of sequences

src/main/java/io/ebeaninternal/server/query/CQueryBuilder.java

@@ -1,5 +1,6 @@
 package io.ebeaninternal.server.query;
 
+import io.ebean.Query;
 import io.ebean.RawSql;
 import io.ebean.RawSqlBuilder;
 import io.ebean.annotation.Platform;
@@ -671,4 +672,16 @@ class CQueryBuilder {
   boolean isPlatformDistinctOn() {
     return dbPlatform.isPlatform(Platform.POSTGRES);
   }
+
+  /**
+   * Return the 'for update' FROM hint (sql server).
+   */
+  public String fromForUpdate(SpiQuery<?> query) {
+    Query.ForUpdate mode = query.getForUpdateMode();
+    if (mode == null) {
+      return null;
+    } else {
+      return dbPlatform.fromForUpdate(mode);
+    }
+  }
 }

src/main/java/io/ebeaninternal/server/query/DefaultDbSqlContext.java

@@ -26,6 +26,8 @@ class DefaultDbSqlContext implements DbSqlContext {
 
   private final ArrayStack<String> prefixStack = new ArrayStack<>();
 
+  private final String fromForUpdate;
+
   private boolean useColumnAlias;
 
   private int columnIndex;
@@ -55,7 +57,8 @@ class DefaultDbSqlContext implements DbSqlContext {
    * Construct for SELECT clause (with column alias settings).
    */
   DefaultDbSqlContext(SqlTreeAlias alias, CQueryBuilder builder,
-                      boolean alwaysUseColumnAlias, CQueryHistorySupport historySupport, CQueryDraftSupport draftSupport) {
+                      boolean alwaysUseColumnAlias, CQueryHistorySupport historySupport,
+                      CQueryDraftSupport draftSupport, String fromForUpdate) {
 
     this.alias = alias;
     this.tableAliasPlaceHolder = builder.tableAliasPlaceHolder;
@@ -64,6 +67,14 @@ class DefaultDbSqlContext implements DbSqlContext {
     this.draftSupport = draftSupport;
     this.historySupport = historySupport;
     this.historyQuery = (historySupport != null);
+    this.fromForUpdate = fromForUpdate;
+  }
+
+  @Override
+  public void appendFromForUpdate() {
+    if (fromForUpdate != null) {
+      append(" ").append(fromForUpdate);
+    }
   }
 
   @Override

src/main/java/io/ebeaninternal/server/query/SqlTreeBuilder.java

@@ -119,9 +119,10 @@ public final class SqlTreeBuilder {
     this.alias = new SqlTreeAlias(request.getBaseTableAlias());
     this.distinctOnPlatform = builder.isPlatformDistinctOn();
 
+    String fromForUpdate = builder.fromForUpdate(query);
     CQueryHistorySupport historySupport = builder.getHistorySupport(query);
     CQueryDraftSupport draftSupport = builder.getDraftSupport(query);
-    this.ctx = new DefaultDbSqlContext(alias, builder, !subQuery, historySupport, draftSupport);
+    this.ctx = new DefaultDbSqlContext(alias, builder, !subQuery, historySupport, draftSupport, fromForUpdate);
   }
 
   /**

src/main/java/io/ebeaninternal/server/query/SqlTreeNodeRoot.java

@@ -68,6 +68,7 @@ final class SqlTreeNodeRoot extends SqlTreeNodeBean {
 
     ctx.append(desc.getBaseTable(temporalMode));
     ctx.append(" ").append(baseTableAlias);
+    ctx.appendFromForUpdate();
 
     if (includeJoin != null) {
       String a1 = baseTableAlias;