improced commit-rollback behaviour on multi-step transactions

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

documents/src/main/java/de/srsoftware/umbrella/documents/SqliteDb.java

@@ -198,11 +198,17 @@ CREATE TABLE IF NOT EXISTS {0} (
 			rs.close();
 			delete().from(TABLE_POSITIONS).where(DOCUMENT_ID,equal(docId)).execute(db);
 			delete().from(TABLE_DOCUMENTS).where(ID,equal(docId)).execute(db);
-			db.setAutoCommit(true);
 			if (number != null) return number;
 			throw failedToDropObject(t(DOCUMENT_WITH_ID, ID,docId));
 		} catch (SQLException e){
+			try {
+				db.rollback();
+			} catch (SQLException ignored){};
 			throw failedToDropObject(t(DOCUMENT_WITH_ID, ID,docId)).causedBy(e);
+		} finally {
+			try {
+				db.setAutoCommit(true);
+			} catch (SQLException ignored){};
 		}
 	}
 
@@ -217,10 +223,16 @@ CREATE TABLE IF NOT EXISTS {0} (
 			stmt.setLong(2,pos);
 			stmt.execute();
 			stmt.close();
-			db.setAutoCommit(true);
 			return pos;
 		} catch (SQLException e) {
+			try {
+				db.rollback();
+			} catch (SQLException ignored){};
 			throw failedToDropObjectFromObject(POSITION,pos,t(Text.DOCUMENT),docId).causedBy(e);
+		} finally {
+			try {
+				db.setAutoCommit(true);
+			} catch (SQLException ignored){};
 		}
 
 	}
@@ -582,9 +594,15 @@ CREATE TABLE IF NOT EXISTS {0} (
 			update(TABLE_POSITIONS).set(POS).where(DOCUMENT_ID,equal(docId)).where(POS,equal(pair.left())).prepare(db).apply(-pair.right()).close();
 			update(TABLE_POSITIONS).set(POS).where(DOCUMENT_ID,equal(docId)).where(POS,equal(pair.right())).prepare(db).apply(pair.left()).close();
 			update(TABLE_POSITIONS).set(POS).where(DOCUMENT_ID,equal(docId)).where(POS,equal(-pair.right())).prepare(db).apply(pair.right()).close();
-			db.setAutoCommit(true);
 		} catch (SQLException e) {
+			try {
+				db.rollback();
+			} catch (SQLException ignored){};
 			throw databaseException(FAILED_TO_SWITCH_POSITIONS,"a",pair.left(),"b",pair.right(),docId).causedBy(e);
+		} finally {
+			try {
+				db.setAutoCommit(true);
+			} catch (SQLException ignored){};
 		}
 		return pair;
 	}