@Override
public Map<String, Object> getUserPreferences(String principalName) {
DynamoDB dynamoDB = new DynamoDB(documentstoreClient.getClient());
Table table = dynamoDB.getTable(USER_PREFERENCES);
Item item = table.getItem(PRINCIPAL_NAME_KEY, principalName);
return item == null ? null : item.asMap();
}
@Override
public Map<String, Object> findInstitutionPreferences() {
DynamoDB dynamoDB = new DynamoDB(documentstoreClient.getClient());
Table table = dynamoDB.getTable(INSTITUTION_PREFERENCES);
Item item = table.getItem(INSTITUTION_ID_KEY, "1232413535");
return item == null ? null : item.asMap();
}
@Override
public void saveUserPreferences(String principalName, String preferences) {
Item item = Item.fromJSON(preferences);
item = item.withString(PRINCIPAL_NAME_KEY, principalName);
DynamoDB dynamoDB = new DynamoDB(documentstoreClient.getClient());
Table table = dynamoDB.getTable(USER_PREFERENCES);
PutItemOutcome outcome = table.putItem(item);
LOG.debug("Saved user preferences: " + outcome);
}
public static void main(String[] args) {
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
client.setEndpoint("http://localhost:8000");
DynamoDB dynamoDB = new DynamoDB(client);
Table table = dynamoDB.getTable("Movies");
HashMap<String, String> nameMap = new HashMap<String, String>();
nameMap.put("#yr", "year");
HashMap<String, Object> valueMap = new HashMap<String, Object>();
valueMap.put(":yyyy", 1985);
QuerySpec querySpec =
new QuerySpec()
.withKeyConditionExpression("#yr = :yyyy")
.withNameMap(new NameMap().with("#yr", "year"))
.withValueMap(valueMap);
ItemCollection<QueryOutcome> items = table.query(querySpec);
Iterator<Item> iterator = items.iterator();
Item item = null;
System.out.println("Movies from 1985");
while (iterator.hasNext()) {
item = iterator.next();
System.out.println(item.getNumber("year") + ": " + item.getString("title"));
}
valueMap.put(":yyyy", 1992);
valueMap.put(":letter1", "A");
valueMap.put(":letter2", "L");
querySpec
.withProjectionExpression("#yr, title, info.genres, info.actors[0]")
.withKeyConditionExpression("#yr = :yyyy and title between :letter1 and :letter2")
.withNameMap(nameMap)
.withValueMap(valueMap);
items = table.query(querySpec);
iterator = items.iterator();
System.out.println("Movies from 1992 - titles A-L, with genres and lead actor");
while (iterator.hasNext()) {
item = iterator.next();
System.out.println(item.toString());
}
}
/** @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// TODO Auto-generated method stub
int change, empty;
String tablename = "ParkingInfo";
HttpSession session = request.getSession();
String LotId = (String) session.getAttribute("lotid");
session.setAttribute("wronginfo", null);
DynamoDB dynamoDB = new DynamoDB(new AmazonDynamoDBClient());
Table table = dynamoDB.getTable(tablename);
Item item = table.getItem("Parkurself", "parkurself", "Id", LotId);
int newe = item.getInt("AvailableSpots");
change = Integer.parseInt(request.getParameter("carsin"));
empty = newe - change;
item.withInt("AvailableSpots", empty);
table.deleteItem("Parkurself", "parkurself", "Id", LotId);
table.putItem(item);
newe = item.getInt("AvailableSpots");
change = Integer.parseInt(request.getParameter("carsout"));
empty = newe + change;
item.withInt("AvailableSpots", empty);
table.deleteItem("Parkurself", "parkurself", "Id", LotId);
table.putItem(item);
newe = item.getInt("AvailableSpots");
if (item.getInt("AvailableSpots") > item.getInt("Total")) {
item.withInt("AvailableSpots", item.getInt("Total"));
table.deleteItem("Parkurself", "parkurself", "Id", LotId);
table.putItem(item);
session.setAttribute("wronginfo", "minus");
} else if (item.getInt("AvailableSpots") < 0) {
int wrongnum = 0 - item.getInt("AvailableSpots");
item.withInt("AvailableSpots", 0);
table.deleteItem("Parkurself", "parkurself", "Id", LotId);
table.putItem(item);
session.setAttribute("wronginfo", "exceed");
session.setAttribute("wrongnum", wrongnum);
}
session.setAttribute("olde", item.get("AvailableSpots"));
session.setAttribute("newe", item.get("AvailableSpots"));
response.sendRedirect("home.jsp");
}
public static void createItems(ChatData chatData) {
Table table = dynamoDB.getTable(tableName);
System.out.println(table.getTableName());
try {
Item item =
new Item()
.withPrimaryKey("TimeStamp", dateNow())
.withString("user", chatData.getUser())
.withString("chat", chatData.getChat());
table.putItem(item);
} catch (Exception e) {
System.err.println("Create items failed.");
System.err.println(e.getMessage());
}
}
// @Test
public void howToDeleteTable() throws InterruptedException {
String TABLE_NAME = "myTableForMidLevelApi";
Table table = dynamo.getTable(TABLE_NAME);
// Wait for the table to become active or deleted
TableDescription desc = table.waitForActiveOrDelete();
if (desc == null) {
System.out.println("Table " + table.getTableName() + " does not exist.");
} else {
table.delete();
// No need to wait, but you could
table.waitForDelete();
System.out.println("Table " + table.getTableName() + " has been deleted");
}
}