Develop Reference

Java AWS DynamoDB how to increment number

I'm trying to add 1 to a number, and then get the new number back.
I can't get my UpdateItemSpec right. Please help. Every example out there seems to show something different and none of it is working.
Here is my code:
AmazonDynamoDBClient dbClient = new AmazonDynamoDBClient(
new BasicAWSCredentials("SECRET", "SECRET")
);
dbClient.setRegion(Region.getRegion(Regions.fromName("us-west-1")));
DynamoDB dynamoDB = new DynamoDB(dbClient);
Table table = dynamoDB.getTable("NumTable");
GetItemSpec spec = new GetItemSpec()
.withPrimaryKey("PKey","OrderNumber");
Item item = table.getItem(spec);
logger.info(item.toJSONPretty());
UpdateItemSpec updateItemSpec = new UpdateItemSpec()
.withPrimaryKey("Pkey",
"OrderNumber")
.withReturnValues("UPDATED_NEW")
.withUpdateExpression("ADD #k :incr")
.withNameMap(new NameMap().with("#k", "NumVal"))
.withValueMap(
new ValueMap()
.withNumber(":incr", 1));
//.withString(":incr", "{N:\"1\"}"));
//I've tried a million other ways too!
UpdateItemOutcome outcome = table.updateItem(updateItemSpec);
logger.info(outcome.getItem().toJSONPretty());
Console shows the first get part working:
Sat Nov 09 00:46:07 UTC - 2019-11-09 00:46:07 f1475303-7585-4804-8a42-2e0a9b16b1dc INFO Commission:88 - {
Sat Nov 09 00:46:07 UTC - "NumVal" : 200000,
Sat Nov 09 00:46:07 UTC - "PKey" : "OrderNumber"
Sat Nov 09 00:46:07 UTC - }
But the update part gives this error (among others):
Sat Nov 09 00:46:08 UTC - The provided key element does not match the schema (Service: AmazonDynamoDBv2; Status Code: 400; Error Code: ValidationException; Request ID: 8TPDT2EVMC0G0GF3IFK7SU6777VV4KQNSO5AEMVJF66Q9ASUAAJG): com.amazonaws.services.dynamodbv2.model.AmazonDynamoDBException com.amazonaws.services.dynamodbv2.model.AmazonDynamoDBException: The provided key element does not match the schema (Service: AmazonDynamoDBv2; Status Code: 400; Error Code: ValidationException; Request ID: 8TPDT2EVMC0G0GF3IFK7SU6777VV4KQNSO5AEMVJF66Q9ASUAAJG) at [........]
I really feel like the key element does match the schema :'(
Here is a picture from my AWS console:

Your implementation looks fine to me. The error is because of typo error in your UpdateItemSpec code.
UpdateItemSpec updateItemSpec = new UpdateItemSpec()
.withPrimaryKey("Pkey",
"OrderNumber")
The typo is "Pkey". It should be "PKey", which is why it works in GetItemSpec code.

How to display omdb function returned value in webpage

Can we store the value returned from omdb function searchOneMovie(moviename) so that it can be displayed as output in JSP page when button is clicked? I am developing a Web-Application where on clicking the button I should get the details of movie as searched by user but by using searchOneMovie() I am getting the output in console not in web page. Please tell how to display searchOneMovie() value in JSP page.
CODE:
public void search(HttpServletResponse response, String moviename) throws OmdbSyntaxErrorException, OmdbConnectionErrorException, OmdbMovieNotFoundException, IOException {
Omdb o = new Omdb();
try {
PrintWriter out = response.getWriter();
out.print(o.searchOneMovie(moviename));
} catch (Exception ignore) {
}
}
OUTPUT: This output is coming on console but i wan't it in webpage please help.
Mar 13, 2017 8:13:51 PM com.omdbapi.RestClient execute
INFO: executing GET http://www.omdbapi.com/?t=star+wars HTTP/1.1
Mar 13, 2017 8:13:52 PM com.omdbapi.Omdb resultToJson
INFO: received {"Title":"Star Wars: Episode IV - A New Hope","Year":"1977","Rated":"PG","Released":"25 May 1977","Runtime":"121 min","Genre":"Action, Adventure, Fantasy","Director":"George Lucas","Writer":"George Lucas","Actors":"Mark Hamill, Harrison Ford, Carrie Fisher, Peter Cushing","Plot":"Luke Skywalker joins forces with a Jedi Knight, a cocky pilot, a wookiee and two droids to save the galaxy from the Empire's world-destroying battle-station, while also attempting to rescue Princess Leia from the evil Darth Vader.","Language":"English","Country":"USA","Awards":"Won 6 Oscars. Another 50 wins & 28 nominations.","Poster":"https://images-na.ssl-images-amazon.com/images/M/MV5BYzQ2OTk4N2QtOGQwNy00MmI3LWEwNmEtOTk0OTY3NDk2MGJkL2ltYWdlL2ltYWdlXkEyXkFqcGdeQXVyNjc1NTYyMjg#._V1_SX300.jpg","Metascore":"92","imdbRating":"8.7","imdbVotes":"963,318","imdbID":"tt0076759","Type":"movie","Response":"True"}

Esper rules for different users

I recently started programming with Esper and I have a smart wearable that sends pedometer data to my laptop. I then process this data using esper. But suppose I have multiple smart wearables with each an unique MAC address. I use time windows and my question is how can I change my rule file so that the rules only fire for events with the same macaddress and take appropiate action based on this MAC address. My initialization and rule are:
Configuration cepConfig = new Configuration();
cepConfig.addEventType("Steps", Steps.class.getName());
// We setup the engine
EPServiceProvider cep = EPServiceProviderManager.getProvider("myCEPEngine", cepConfig);
EPRuntime cepRT = cep.getEPRuntime();
// We register an EPL statement
EPAdministrator cepSteps1 = cep.getEPAdministrator();
EPStatement cepStatementSteps1 = cepSteps1.createEPL("select * from "
+ "Steps().win:time(1 hour) "
+ "group by macAddress "
+ "having sum(max(steps)-min(steps)) < 100");
cepStatementSteps1.addListener(new rule1Listener());
My Steps class has the following fields:
double steps;
String stepsTimestamp;
String macAddress;
And this is how I insert the events:
Steps steps0 = new Steps(0, new Date(timeStamp).toString(), "K5E45H778");
cepRT.sendEvent(steps0);
Steps steps00 = new Steps(0, new Date(timeStamp).toString(), "LD24ESF74");
cepRT.sendEvent(steps00);
Steps steps1 = new Steps(25, new Date(timeStamp).toString(), "K5E45H778");
cepRT.sendEvent(steps1);
Steps steps2 = new Steps(50, new Date(timeStamp).toString(), "LD24ESF74");
cepRT.sendEvent(steps2);
Steps steps3 = new Steps(55, new Date(timeStamp).toString(), "K5E45H778");
cepRT.sendEvent(steps3);
Steps steps4 = new Steps(105, new Date(timeStamp).toString(), "LD24ESF74");
cepRT.sendEvent(steps4);
Steps steps5 = new Steps(75, new Date(timeStamp).toString(), "K5E45H778");
cepRT.sendEvent(steps5);
Steps steps6 = new Steps(110, new Date(timeStamp).toString(), "K5E45H778");
cepRT.sendEvent(steps6);
This is my output:
Sending tick: Steps: 0.0 Timestamp: Mon Mar 14 18:13:23 CET 2016 Mac Address: K5E45H778
->Rule 1 fired: K5E45H778
Sending tick: Steps: 0.0 Timestamp: Mon Mar 14 18:18:23 CET 2016 Mac Address: LD24ESF7474
->Rule 1 fired: LD24ESF7474
Sending tick: Steps: 25.0 Timestamp: Mon Mar 14 18:23:23 CET 2016 Mac Address: K5E45H778
->Rule 1 fired: K5E45H778
Sending tick: Steps: 105.0 Timestamp: Mon Mar 14 18:28:23 CET 2016 Mac Address: LD24ESF7474
Sending tick: Steps: 55.0 Timestamp: Mon Mar 14 18:33:23 CET 2016 Mac Address: K5E45H778
->Rule 1 fired: K5E45H778
Sending tick: Steps: 75.0 Timestamp: Mon Mar 14 18:38:23 CET 2016 Mac Address: K5E45H778
Sending tick: Steps: 110.0 Timestamp: Mon Mar 14 18:43:23 CET 2016 Mac Address: K5E45H778
Why doesn't the rule fire for the one but last event of 75 steps?

The SQL-standard "group by" clause is for aggregation per group. Thus just adding "group by macAddress" should get it done.

OutputSream.write is too slow

I am encountering with a senerior like this:
My project has a servlet to catch a request from perl. The request is to download a file. The request is a multipartRequest.
#RequestMapping(value = "/*", method = RequestMethod.POST)
public void tdRequest(#RequestHeader("Authorization") String authenticate,
HttpServletResponse response,
HttpServletRequest request) throws Exception
{
if (ServletFileUpload.isMultipartContent(request))
{
ServletFileUpload sfu = new ServletFileUpload();
FileItemIterator items = sfu.getItemIterator(request);
while (items.hasNext())
{
FileItemStream item = items.next();
if (("action").equals(item.getFieldName()))
{
InputStream stream = item.openStream();
String value = Streams.asString(stream);
if (("upload").equals(value))
{
uploadRequest(items, response);
return;
}
else if (("download").equals(value))
{
downloadRequest(items, response);
return;
}
The problem is not here, it appears on the downloadRequest() function.
void downloadRequest(FileItemIterator items,
HttpServletResponse response) throws Exception
{
log.info("Start downloadRequest.......");
OutputStream os = response.getOutputStream();
File file = new File("D:\\clip.mp4");
FileInputStream fileIn = new FileInputStream(file);
//while ((datablock = dataOutputStreamServiceImpl.readBlock()) != null)
byte[] outputByte = new byte[ONE_MEGABYE];
while (fileIn.read(outputByte) != -1)
{
System.out.println("--------" + (i = i + 1) + "--------");
System.out.println(new Date());
//dataContent = datablock.getContent();
System.out.println("Start write " + new Date());
os.write(outputByte, 0,outputByte.length);
System.out.println("End write " + new Date());
//System.out.println("----------------------");
}
os.close();
}
}
I try to read and write blocks of 1MB from the file. However, it takes too long for downloading the whole file. ( my case is 20mins for file of 100MB)
I try to sysout and I saw a result like this:
The first few blocks can read, write data realy fast:
--------1--------
Mon Dec 07 16:24:20 ICT 2015
Start write Mon Dec 07 16:24:20 ICT 2015
End write Mon Dec 07 16:24:21 ICT 2015
--------2--------
Mon Dec 07 16:24:21 ICT 2015
Start write Mon Dec 07 16:24:21 ICT 2015
End write Mon Dec 07 16:24:21 ICT 2015
--------3--------
Mon Dec 07 16:24:21 ICT 2015
Start write Mon Dec 07 16:24:21 ICT 2015
End write Mon Dec 07 16:24:21 ICT 2015
But the next block is slower than the previous
--------72--------
Mon Dec 07 16:29:22 ICT 2015
Start write Mon Dec 07 16:29:22 ICT 2015
End write Mon Dec 07 16:29:29 ICT 2015
--------73--------
Mon Dec 07 16:29:29 ICT 2015
Start write Mon Dec 07 16:29:29 ICT 2015
End write Mon Dec 07 16:29:37 ICT 2015
--------124--------
Mon Dec 07 16:38:22 ICT 2015
Start write Mon Dec 07 16:38:22 ICT 2015
End write Mon Dec 07 16:38:35 ICT 2015
--------125--------
Mon Dec 07 16:38:35 ICT 2015
Start write Mon Dec 07 16:38:35 ICT 2015
End write Mon Dec 07 16:38:48 ICT 2015
The problem is in the os.write()
I realy cannot understand how the outputStream write, why it take such a long time like that? or I made some mistakes?
Sorry for my bad english. I realy need your support. Thank in advance!
This is the perl code from the client side
# ----- get connected to download the file
#
$Response = $ua->request(POST $remoteHost ,
Content_Type => 'form-data',
Authorization => $Authorization,
'Proxy-Authorization' => $Proxy_Authorization ,
Content => [ DOS => 1 ,
action => 'download' ,
first_run => 0 ,
dl_filename => $dl_filename ,
delivery_dir => $delivery_dir ,
verbose => $Verbose ,
debug => $debug ,
version => $VERSION
]
);
unless ($Response->is_success) {
my $Msg = $Response->error_as_HTML;
# Remove HTML tags - we're in a DOS shell!
$Msg =~ s/<[^>]+>//g;
print "ERROR! SERVER RESPONSE:\n$Msg\n";
print "$remoteHost\n\n" if $Options{'v'};
Error "Could not connect to " . $remoteHost ;
}
my $Result2 = $Response->content();
Error "Abnormal termination...\n$Result2" if $Result2 =~ /_APP_ERROR_/;
open(F, ">$dl_filename") or Error "Could not open '$dl_filename'!";
binmode F; # unless $dl_filename =~ /\.txt$|\.htm$/;
print F $Result2;
close F;
print "received.\n";
}

One problem is that fileIn.read(outputByte) can read random number of bytes, not only full outputByte. You read few KB, then you store full 1MB, and very fast you are running out of space on disk. Try this, notice the "readed" parameter.
void downloadRequest(FileItemIterator items,
HttpServletResponse response) throws Exception
{
log.info("Start downloadRequest.......");
OutputStream os = response.getOutputStream();
File file = new File("D:\\clip.mp4");
FileInputStream fileIn = new FileInputStream(file);
//while ((datablock = dataOutputStreamServiceImpl.readBlock()) != null)
byte[] outputByte = new byte[ONE_MEGABYE];
int readed =0;
while ((readed =fileIn.read(outputByte)) != -1)
{
System.out.println("--------" + (i = i + 1) + "--------");
System.out.println(new Date());
//dataContent = datablock.getContent();
System.out.println("Start write " + new Date());
os.write(outputByte, 0,readed );
System.out.println("End write " + new Date());
//System.out.println("----------------------");
}
os.close();
}
}

It looks like your download performance gets slower and slower, the further you are getting into the download. You start out at one or less seconds per block, by block 72 it is 7+ seconds per block and by block 128 it is 13 seconds per block.
There is nothing on the server side to explain this. Rather, it has the "smell" of the client side doing something wrong. My guess is that the client side is reading the data from the socket into an in-memory data structure, and that data structure (maybe just a String or StringBuffer or StringBuilder) is getting larger and larger. Either the time take to expand it is getting larger, or your memory footprint is growing and the GC is taking longer and longer. (Or both.)
If you showed us the client-side code .....
UPDATE
As I suspected, this line of code will be reading the entire content into the Perl equivalent of a string builder before turning it into a string.
my $Result2 = $Response->content();
Depending on how it is implemented under the hood, this will lead to repeated copying of the data as the builder runs out of buffer space and needs to be expanded. Depending on the buffer expansion strategy that Perl employs for this, it could give O(N^2) behavior, where N is the size of the file you are transferring. (The evidence is that you are not getting O(N) behavior ...)
If you want a faster downloads, you need to stream the data on the client side. Read the response content in chunks and write them to the output file. (I'm not a Perl expert, so I can't offer you code.) This will also reduce the memory footprint on the client side ... which could be important if your file sizes increase.

Not able to change quantity of a commerceItem using handleSetOrderByCommerceId

I am not able to change the quantity of commerceItem using handleSetOrderByCommerceId.PFB.
I am using Art Technology Group web commerce platform.
Here is my code snippet:
for (CommerceItem cI : commerceItems) {
if (isLoggingDebug()) {
logDebug("inside handleRemoveItemFromOrder : commerceItems iteration : "+cI.getId() +" : "+ cI.getCatalogRefId());
}
request.setParameter(cI.getId(), cI.getQuantity());
if(cI.getCatalogRefId().equals(dealTobeDeleted)){
long quantity = cI.getQuantity();
//String currentSku = cI.getCatalogRefId();
if(quantity > 1){
// Set the new quantity for the commerce item being updated.
request.setParameter(cI.getCatalogRefId(), quantity-1);
setCheckForChangedQuantity(true);
result = super.handleSetOrderByCommerceId(request, response);
if (isLoggingDebug()) {
logDebug("inside handleRemoveItemFromOrder : after super call handleSetOrderByCommerceId : "+result);
}
}else{
String[] dealArray = new String[]{cI.getId()};
repoItemIdOfCommerceItemGettingRemoved = cI.getCatalogRefId();
setRemovalCommerceIds(dealArray);
if (isLoggingDebug()) {
logDebug("inside handleRemoveItemFromOrder : before super call handleRemoveItemFromOrder : "+repoItemIdOfCommerceItemGettingRemoved +" : "+getRemovalCommerceIds().length);
}
break;
}
}
}
The logs says :
**** debug Fri Sep 18 15:49:55 CAT 2015 1442584195886 /atg/dynamo/servlet/pipeline/RequestScopeManager/RequestScope-37/atg/commerce/order/purchase/CartModifierFormHandler no form errors - staying on same page.
**** debug Fri Sep 18 15:49:55 CAT 2015 1442584195886 /atg/dynamo/servlet/pipeline/RequestScopeManager/RequestScope-37/atg/commerce/order/purchase/CartModifierFormHandler no form errors - staying on same page.
**** info Fri Sep 18 15:49:55 CAT 2015 1442584195889 /com/cellc/online/commerce/pricing/calculators/OrderMonthlyCostCalculator monthlyPrice::::::::::::::509.0
**** debug Fri Sep 18 15:49:55 CAT 2015 1442584195889 /atg/dynamo/servlet/pipeline/RequestScopeManager/RequestScope-37/atg/commerce/order/purchase/CartModifierFormHandler runProcess skipped because chain ID is null
**** debug Fri Sep 18 15:49:55 CAT 2015 1442584195889 /atg/dynamo/servlet/pipeline/RequestScopeManager/RequestScope-37/atg/commerce/order/purchase/CartModifierFormHandler no form errors - staying on same page.
**** debug Fri Sep 18 15:49:55 CAT 2015 1442584195889 /atg/commerce/order/OrderManager Order: o8950004 Version in object: 183 Version in repItem: 183
**** debug Fri Sep 18 15:49:56 CAT 2015 1442584196206 /atg/dynamo/servlet/pipeline/RequestScopeManager/RequestScope-37/atg/commerce/order/purchase/CartModifierFormHandler no form errors - staying on same page.