public void howToPutItems() {
Table table = dynamo.getTable(TABLE_NAME);
Item item = new Item()
.withPrimaryKey(HASH_KEY_NAME, "B_PutItemJsonTest", RANGE_KEY_NAME, 1)
// Store document as a map
.withMap("document", new ValueMap()
.withString("last_name", "Bar")
.withString("first_name", "Jeff")
.withString("current_city", "Tokyo")
.withMap("next_haircut",
new ValueMap()
.withInt("year", 2014)
.withInt("month", 10)
.withInt("day", 30))
.withList("children", "SJB", "ASB", "CGB", "BGB", "GTB")
);
table.putItem(item);
// Retrieve the entire document and the entire document only
Item documentItem = table.getItem(new GetItemSpec()
.withPrimaryKey(HASH_KEY_NAME, "B_PutItemJsonTest", RANGE_KEY_NAME, 1)
.withAttributesToGet("document"));
System.out.println(documentItem.get("document"));
// Output: {last_name=Bar, children=[SJB, ASB, CGB, BGB, GTB], first_name=Jeff, current_city=Tokyo, next_haircut={month=10, year=2014, day=30}}
// Retrieve part of a document. Perhaps I need the next_haircut and nothing else
Item partialDocItem = table.getItem(new GetItemSpec()
.withPrimaryKey(HASH_KEY_NAME, "B_PutItemJsonTest", RANGE_KEY_NAME, 1)
.withProjectionExpression("document.next_haircut"))
;
System.out.println(partialDocItem);
// Output: { Item: {document={next_haircut={month=10, year=2014, day=30}}} }
// I can update part of a document. Here's how I would change my current_city back to Seattle:
table.updateItem(new UpdateItemSpec()
.withPrimaryKey(HASH_KEY_NAME, "B_PutItemJsonTest", RANGE_KEY_NAME, 1)
.withUpdateExpression("SET document.current_city = :city")
.withValueMap(new ValueMap().withString(":city", "Seattle"))
);
// Retrieve the entire item
Item itemUpdated = table.getItem(HASH_KEY_NAME, "B_PutItemJsonTest", RANGE_KEY_NAME, 1);
System.out.println(itemUpdated);
// Output: { Item: {document={last_name=Bar, children=[SJB, ASB, CGB, BGB, GTB], first_name=Jeff, current_city=Seattle, next_haircut={month=10, year=2014, day=30}}, myRangeKey=1, myHashKey=B_PutItemJsonTest} }