I have a data provider, where I can run a query that looks like this, to get prices. Please assume getPrices is defined.
void batchGet(String[] s,ObservableEmitter<Map<String,Double> y){
List<List<String>> prts = Lists.partition(Lists.newArrayList(s), BATCH_SIZE);
for(List<String>batchList : prts ) {
String[] batch = new String[batchList.size()];
batchList.toArray(batch);
try {
Map<String, Double> res = getPrices(batch);
y.onNext(res );
} catch (IOException e) {
y.onError(e);
}
}
y.onComplete();
}
I am calling the method above using the following code:
Observable<Quote> ret = Observable.create(y -> {
batchGet(symbols, y)});
ret.subscribe(q -> saveQuotes(q));
later, I noticed that there was a NullPointerException when y.onNext(...)
is called, due to y==null. What am I doing wrong?
Thank you
Related
I am using VS 2022, Blazor server project. When I trying to save data
async public static Task<bool> updateObject(Firecall obj)
{
Firecall r;
try
{
using (var context = new sptContext())
{
r = context.Firecalls.Where(c => c.Mguid == obj.Mguid).FirstOrDefault();
bool новое = (r == null);
if (новое)
{
r = new Firecall();
}
r.comment = obj.comment;
if (новое)
await context.Firecalls.AddAsync(r);
if (busy)
return false;
try
{
busy = true;
await context.SaveChangesAsync();
}
catch (Exception)
{
return false;
}
finally {
busy = false;
}
}
return true;
}
catch (Exception)
{
return false;
}
}
sometimes I get error:
Sometimes an error occurs, sometimes not. No error in debugger.
How to solve problem?
P.S. Data in each operation is saved as expected. Only after the operation is completed the indicated error message appear
And calling savechanges method from #code block of .razor view:
async private void SaveChanges()
{
bool rez = await firecallRepository.updateObject(_currentFireCall);
}
I have code snippet below.
What I want is if getNames() method catch an exception
( ex. InterruptedException ),
want to check if Got InterruptedException !!! prints out or not.
There are some examples of testing exception for a method
which throws an exception in its method ( ex. String method1() throws InterruptedException {...} ) in the Internet.
But not this case. Does anyone have some thought or idea?
public class A {
public List<String> getNames()
{
String addess = "address1";
int age = 17;
List<String> names = null;
try {
names = getSomeNames(address, sex);
}
catch (InterruptedException | ExecutionException e) {
throw new MyCustomException(e);
}
catch(Exception e) {
throw new MyCustomException(e);
}
return names;
}
List<String> getSomeNames(String address, int sex) throws InterruptedException, ExecutionException
{
// ...
// throw exceptions... at some point
//
return names;
}
}
public class MyCustomException extends Exception {
public MyCustomException(Throwable e) {
if (e.getCause() instanceof InterruptedException) {
// write log
System.out.println("Got InterruptedException !!!");
}
else if (e.getCause() instanceof ExecutionException) {
// write log
System.out.println("Got ExecutionException!!!");
}
else {
// write log
}
}
}
I tried this but the test failed and got NullPointerException in catch block.
#Test
public void testException() {
A objA = spy(new A());
try {
doThrow(MyCustomException.class).when(objA).getNames();
objA.getNnames();
}
catch (Exception e) {
System.out.println(e.getCause().toString()); // ==> throws java.lang.NullPointerException here.
}
}
There are several ways to test it.
First solution is to replace System.out with different stream and read from it later. ( I don't like this approach )
#Test
void whenSayHi_thenPrintlnCalled() throws IOException {
PrintStream normalOutput = System.out;
String result;
try (ByteArrayOutputStream baos = new ByteArrayOutputStream(); PrintStream temporalOutput = new PrintStream(baos)) {
System.setOut(temporalOutput);
ThatGuy thatGuy = new ThatGuy();
thatGuy.sayHi();
result = new String(baos.toByteArray(), StandardCharsets.UTF_8);
} finally {
System.setOut(normalOutput);
}
assertEquals("Hi", result.trim());
}
Second one is to use logger instead of just System.out. I consider this approach better not only from testing, but from code design perspective as well. Using this one you can just replace logger with Mockito.mock and user Mockito.verify to check what was called on your logger.
#Test
void whenSayHi_thenCallLogger() {
Logger logger = Mockito.mock(Logger.class);
ThatGuy thatGuy = new ThatGuy();
ReflectionTestUtils.setField(thatGuy, "logger", logger);
thatGuy.sayHiToLog();
verify(logger).error("Hi");
}
Class under testing looks like this:
class ThatGuy {
private static Logger logger = LoggerFactory.getLogger(ThatGuy.class);
void sayHi() {
System.out.println("Hi");
}
void sayHiToLog() {
logger.error("Hi");
}
}
I want to use blocking handler, but still get an error:
java.lang.IllegalStateException: Response has already been written
Here is my code:
Server.java
r.route("/api/details/send/").handler(BodyHandler.create());
r.route("/api/details/send/").handler(ctx-> {
JsonArray ja = ctx.getBodyAsJsonArray();
JsonArray params = new JsonArray();
vertx.executeBlocking(futur -> {
for(int i =0; i<ja.size();i++) {
JsonObject req = new JsonObject();
req.put("QUERY", "INSERT INTO detailsfacture VALUES ('',?,?,?,?,?,?,?)");
req.put("DB", "MYSQL_");
params.add(ja.getJsonObject(i).getValue("typefacture"))
.add(ja.getJsonObject(i).getValue("activites"))
.add(Integer.parseInt(ja.getJsonObject(i).getValue("qte").toString()))
.add(Double.parseDouble(ja.getJsonObject(i).getValue("pu").toString())
.add(ja.getJsonObject(i).getValue("unite"))
.add(Double.parseDouble(ja.getJsonObject(i).getValue("montant").toString())
.add(ja.getJsonObject(i).getValue("codefacture"));
req.put("PARAMS", params);
eb.send("EXECUTE", req, res -> {
if (res.succeeded()) {
params.clear();
ctx.response().putHeader("content-type", "application/json").end(res.result().body().toString());
} else {
ctx.response().putHeader("content-type", "application/json").end(res.cause().getMessage());
}
});
}
String result = "orsys";
futur.complete(result);
},resultat->{
ctx.response().putHeader(HttpHeaders.CONTENT_TYPE, "text/plain");
//resultat.result().toString();
});
});
MySql.java
eb.consumer("MYSQL_EXECUTE_WITH_PARAMS", req->{
try{
JsonObject reqParams = (JsonObject)req.body();
String sql = reqParams.getString("QUERY");
client.getConnection( connection -> {
if (connection.succeeded()) {
try{
SQLConnection con = connection.result();
con.updateWithParams(sql,reqParams.getJsonArray("PARAMS"), query -> {
if(query.succeeded()){
UpdateResult urs = query.result();
req.reply(urs.toJson());
//req.reply(query.result());
}else{
req.fail(24, "Err Request : "+query.cause().getMessage());
}
});
}catch(Exception e){
req.fail(24, "Err Conn Failed : "+e.getMessage());
}
} else {
req.fail(24, "Err No Connection : "+connection.cause().getMessage());
}
});
}catch(Exception e){
req.fail(24, e.getMessage());
}
});
P.S. : When I remove executeBlocking only the first records is registred in my database.
Regards.
You insert entities into detailsfacture in a loop. For each insert you call following:
ctx.response().putHeader("content-type", "application/json").end(res.result().body().toString());
As you can see you call the end(...) method of the response object. Thats where the IllegalStateException comes from. As the documentation states:
Once the response has ended, it cannot be used any more.
So you problem has nothing to do with the executeBlocking.
You should take a look at the write(...) method of HttpServerResponse. For each insert you should call write(...) instead of end(...). But this will only work if you know the complete length of the whole response because you need to set the header Content-length. If you are finished with all inserts you need to call end() to complete the response. Also you should only set the header once and not for each insert.
Now some additional comments. I don't see the need for executeBlocking in your case. Because of the problem with Content-length I recommend to wrap each insert with a Future and compose all of them with CompositeFuture. The Future futur is used the wrong way. The send(...) method of Event bus is not blocking and asynchronous. So the futur.complete(result) is called right after you send all your inserts. Also it's strange that the consumer consumes MYSQL_EXECUTE_WITH_PARAMS and the send sends to EXECUTE.
I tried another solution to get my query like that (?,?,...,?),(?,?,...,?),..,(?,?,...,?).
Here is my code :
public static String getMultipleInsertReq(String table, JsonArray columns,JsonArray data){
JsonObject tab= Tables.Tables_list.getJsonObject(table); // name of table
String sql = "";
if(tab != null){
sql = "INSERT INTO "+table + "( ";
if(columns == null){
columns = tab.getJsonArray("COLS"); //columns from ur database
}
if(columns!=null){
for(int i=0;i<columns.size();i++){
if(i==columns.size()-1){
sql+=columns.getString(i)+") VALUES";
}
else{
sql+=columns.getString(i)+",";
}
}
for(int i =0; i<data.size();i++){
for(int j=0; j<columns.size();j++){
if(j==columns.size()-1 && i!=data.size()-1){
sql+="?),";
}
else if (i==data.size()-1 && j==columns.size()-1){
sql+="?)";
}
else if (j==0){
sql+="(?,";
}
else{
sql+="?,";
}
}
}
return sql;
}
}
return null;
}
Hope it helps.
P.S.: it's only a query builder so you can adapt it depending on your needs.
Regards.
I would like to test a method, in JUnit4, that does not pass at the first caught exception, but if all calls to the tested method throw exception. And I would like to know if this is possible.
I explain : let us say I have the method
public void setFromFen(String fenValue) throws IllegalArgumentException
in a class Position.
In PositionTest Junit4 class, I would like to do something like this :
#Test(expected=IllegalArgumentException.class){
...
setFromFen("2"); // throws IllegalArgumentException
setFromFen("8/8/8/8/8/8/8/8"); // does not throw IllegalArgumentException
...
}
so that the test only succeed if all calls to setFromFen fail.
In this case, though the second test does not throw IllegalArgumentException, the test succeed : and that's not what I want.
Is is it possible to get success only if all tests lines throws IllegalArgumentException ?
I think this is outside of the possibilities of the annotation.
You'll probably need something along these lines:
#Test
public void thatAllCallsFail() {
int failureCount = 0;
try {
setFromFen(this.sampleString1);
}
catch( final Exception e ) {
failureCount++;
}
try {
setFromFen(this.sampleString1);
}
catch( final Exception e ) {
failureCount++;
assertEquals("All 2 calls should have failed", failureCount, 2);
}
}
I'm not for a second suggesting that that is a nice way of doing it.
If you're looking for a more generic solution, perhaps adding your strings to a collection and looping over them...
#Test
public void thatAllCallsFail2() {
final String[] strings = new String[] { sampleString1, sampleString2 };
int failureCount = 0;
for (final String string : strings) {
try {
setFromFen(string);
}
catch( final Exception e ) {
failureCount++;
}
}
assertEquals("All " + strings.length + " calls should have failed", failureCount, strings.length);
}
Of course, neither of these solutions will tell you which call did not throw an exception if the tests were to fail.
I have this method that tries to get a list of things:
private static IQueryable<Thing> GetThings(int thingsType)
{
try
{
return from thing in entities.thing.Include("thingStuff")
select thing;
}
catch (Exception exception)
{
return new EnumerableQuery<Thing>(?????);
}
}
}
I want to return an empty IQueryable if I can't for whatever reason get the query to run. I don't want to return NULL because that could break the calling code. Is it possible or am I going totally wrong about this?
These answers are good and do work, however I have always felt using Empty and not creating a new List is cleaner:
Enumerable.Empty<Thing>().AsQueryable();
Try the following:
private static IQueryable<Thing> GetThings(int thingsType)
{
IQueryable<Thing> things = new List<Thing>().AsQueryable();
try
{
things = from thing in entities.thing.Include("thingStuff")
select thing;
return things;
}
catch (Exception exception)
{
return things;
}
}
I would add block finally {} and put my return type in that code.
This will take care of the issue by returning the type that your application expects.
private static IQueryable<T> GetThings(int thingsType)
{
IQueryable<T> list = new List<Thing>().AsQueryable();
try
{
list = from thing in entities.thing.Include("thingStuff")
select t;
}
catch (Exception exception)
{
// handle exception here;
}
finally {
return list;
}
}
}
Returning empty IQueryable<>
DbSet.Take(0)
I think this would be tidier:
private static IQueryable<T> GetThings(int thingsType)
{
try
{
return from thing in entities.thing.Include("thingStuff")
select t;
}
catch (Exception exception)
{
// Exception handling code goes here
return new List<Thing>().AsQueryable();
}
}