#275 - ENH: Add support for @SequenceGenerator initialValue and allocationSize

src/main/java/com/avaje/ebean/config/dbplatform/DatabasePlatform.java

@@ -424,4 +424,23 @@ public class DatabasePlatform {
   public boolean isDisallowBatchOnCascade() {
     return disallowBatchOnCascade;
   }
+
+  /**
+   * Generate and return the create sequence DDL.
+   */
+  public String ddlCreateSequence(String sequenceName, int initialValue, int allocationSize) {
+
+    StringBuilder sb = new StringBuilder("create sequence ");
+    sb.append(sequenceName);
+    if (initialValue > 1) {
+      sb.append(" start with ").append(initialValue);
+    }
+    if (allocationSize > 0 && allocationSize != 50) {
+      // at this stage ignoring allocationSize 50 as this is the 'default' and
+      // not consistent with the way Ebean batch fetches sequence values
+      sb.append(" increment by ").append(allocationSize);
+    }
+    sb.append(";");
+    return sb.toString();
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/ddl/CreateSequenceVisitor.java

@@ -36,12 +36,14 @@ public class CreateSequenceVisitor implements BeanVisitor {
 				+" as DatabasePlatform does not support sequences";
 			logger.warn(msg);
 			return false;
-		} 
+		}
 
-		if (descriptor.getSequenceName() != null) {
-			ctx.write("create sequence ");
-			ctx.write(descriptor.getSequenceName());			
-			ctx.write(";").writeNewLine().writeNewLine();
+		String sequenceName = descriptor.getSequenceName();
+		if (sequenceName != null) {
+			int initialValue = descriptor.getSequenceInitialValue();
+			int allocationSize = descriptor.getSequenceAllocationSize();
+			String createSeq = ctx.getDbPlatform().ddlCreateSequence(sequenceName, initialValue, allocationSize);
+			ctx.write(createSeq).writeNewLine().writeNewLine();
 		}
 		return true;
 	}

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanDescriptor.java

@@ -92,6 +92,10 @@ public class BeanDescriptor<T> implements MetaBeanInfo {
    */
   private final String sequenceName;
 
+  private final int sequenceInitialValue;
+
+  private final int sequenceAllocationSize;
+
   /**
    * SQL used to return last inserted id. Used for Identity columns where
    * getGeneratedKeys is not supported.
@@ -332,6 +336,8 @@ public class BeanDescriptor<T> implements MetaBeanInfo {
     this.idType = deploy.getIdType();
     this.idGenerator = deploy.getIdGenerator();
     this.sequenceName = deploy.getSequenceName();
+    this.sequenceInitialValue = deploy.getSequenceInitialValue();
+    this.sequenceAllocationSize = deploy.getSequenceAllocationSize();
     this.selectLastInsertedId = deploy.getSelectLastInsertedId();
     this.lazyFetchIncludes = InternString.intern(deploy.getLazyFetchIncludes());
     this.concurrencyMode = deploy.getConcurrencyMode();
@@ -1686,6 +1692,20 @@ public class BeanDescriptor<T> implements MetaBeanInfo {
     return sequenceName;
   }
 
+  /**
+   * Return the sequence initial value.
+   */
+  public int getSequenceInitialValue() {
+    return sequenceInitialValue;
+  }
+
+  /**
+   * Return the sequence allocation size.
+   */
+  public int getSequenceAllocationSize() {
+    return sequenceAllocationSize;
+  }
+
   /**
    * Return the SQL used to return the last inserted id.
    * <p>

src/main/java/com/avaje/ebeaninternal/server/deploy/meta/DeployBeanDescriptor.java

@@ -91,6 +91,10 @@ public class DeployBeanDescriptor<T> {
    */
   private String sequenceName;
 
+  private int sequenceInitialValue;
+
+  private int sequenceAllocationSize;
+
   /**
    * Used with Identity columns but no getGeneratedKeys support.
    */
@@ -263,6 +267,22 @@ public class DeployBeanDescriptor<T> {
     return entityType;
   }
 
+  public void setSequenceInitialValue(int sequenceInitialValue) {
+    this.sequenceInitialValue = sequenceInitialValue;
+  }
+
+  public void setSequenceAllocationSize(int sequenceAllocationSize) {
+    this.sequenceAllocationSize = sequenceAllocationSize;
+  }
+
+  public int getSequenceInitialValue() {
+    return sequenceInitialValue;
+  }
+
+  public int getSequenceAllocationSize() {
+    return sequenceAllocationSize;
+  }
+
   public void add(DRawSqlMeta rawSqlMeta) {
     rawSqlMetas.put(rawSqlMeta.getName(), rawSqlMeta);
     if ("default".equals(rawSqlMeta.getName())) {

src/main/java/com/avaje/ebeaninternal/server/deploy/parse/AnnotationFields.java

@@ -349,6 +349,8 @@ public class AnnotationFields extends AnnotationParser {
       if (sequenceGenerator.name().equals(genName)) {
         genName = sequenceGenerator.sequenceName();
       }
+      descriptor.setSequenceInitialValue(sequenceGenerator.initialValue());
+      descriptor.setSequenceAllocationSize(sequenceGenerator.allocationSize());
     }
 
     GenerationType strategy = gen.strategy();