GraphTraversal<Vertex, Map<String, Object>> tsList = traversalSource.V().has("request","id_key",114).valueMap();
while(tsList.hasNext())
{
System.out.println(tsList.next().get("status")); //prints result
System.out.println(tsList.next().get("tree_id_key")); //prints result
System.out.println(tsList.next().get("username")); //here throws Exception for any vertex.
System.out.println(tsList.next().get("tree_status"));
}
when I run the above query, I am getting values for any first and second propertyKey. but after getting answers for two Keys It throws NoFastSuchElementException for any propertyKey...Kindly help me..how can I resolve this?
but using below query I am able to get the answer:
GraphTraversal<Vertex, Map<String, Object>> tsList = traversalSource.V().has("request","id_key",114).values("status","tree_id_key","username","tree_status");
while(tsList.hasNext())
{
System.out.println(tsList.next());//prints "status" value
System.out.println(tsList.next());//prints "tree_id_key" value
System.out.println(tsList.next());//prints "username" value
System.out.println(tsList.next());//prints "tree_status" value
}
updated:
GraphTraversal<Vertex, Map<String, Object>> ts = traversalSource.V().has("request","id_key",113).valueMap();
while(ts.hasNext())
{
Map<String, Object> tsList=ts.next();
SuiteIdKey=(long)((ArrayList)tsList.get("suiteKey")).get(0);
seqe=(int)((ArrayList)tsList.get("sequence")).get(0);
}
In the above query, ts will return many rows and for each row I will get suiteIdkey,seqe..I am able to get the answer. But tsList is Map<>, it is not directly returning answer when I use like this =(long)tsList.get("suiteKey"), without ArrayList. Is it the correct way? Kindly help me.
You are asking for two different things in those two traversals. The first one with valueMap() asks that the vertex be converted to a Map, so you don't want to keep calling next() in that loop. Just do:
Map<String, List<Object>> m = traversalSource.V().has("request", "id_key", 114).
valueMap().next();
System.out.println(m.get("status").get(0));
System.out.println(m.get("tree_id_key").get(0));
System.out.println(m.get("username").get(0));
System.out.println(m.get("tree_status").get(0));
Keep in mind above that i'm assuming your traversal always returns one vertex...account for that otherwise if that is not true.
In your second traversal where you do values() you are asking Gremlin to convert grab the values of those specific properties on that vertex and stream them out and thus you need to iterate with multiple calls to next.
Note that typically returning the entire vertex object isn't a recommended practice. It is somewhat akin to SELECT * FROM table in SQL. It is better to get only the fields that you want to get which then gets rid of the ugly multi-property issue of Map<String, List<Object>>:
Map<String, Object> m = traversalSource.V().has("request", "id_key", 114).
project('s`,'tik', 'u', 'ts').
by('status').
by('tree_id_key').
by('username')
by('tree_status').
next();
System.out.println(m.get("s"));
System.out.println(m.get("tik"));
System.out.println(m.get("u"));
System.out.println(m.get("ts"));
Related
I am reusing the following optional optionalData which is declared and validated a few lines above.
If I reach here, this optional is definitely not empty.
The following code works fine as intended where I am putting and deleting some data.
Question is, is this the correct way to do it where I am using a map and not doing anything with the returned data?
Cos I am having to return a value here when I am actually not doing anything with it.
Only reason I am returning is cos there is a syntax error if I don't.
optionalData
.map(artData -> {
Map<String, Object> currentData = artData.get(idKey);
artData.remove(idKey);
artData.put(getId(previousData), currentData);
return artData.get(getId(previousData));
});
The correct way would be to use Optional::ifPresent instead of Optional::map. The code would then transform to
optionalData
.ifPresent(artData -> {
Map<String, Object> currentData = artData.get(idKey);
artData.remove(idKey);
artData.put(getId(previousData), currentData);
});
I need to create a mongotemplate database query to get a specific number of elements into a list.
At the moment I just get all the elements with findAll(), and then I modify the obtained data using code that I have writen within the service class.
Initially, I have a Laptop class with fields price::BigDecimal and name::String and I use findAll() to get a list of them.
Then I put those in a HashMap, where key is the name field, sorted from most expensive to cheapest.
Map<String, List<Laptop>> laptopsMap = laptopsFrom.stream()
.collect(Collectors.groupingBy(Laptop::getName,
Collectors.collectingAndThen(Collectors.toList(),
l -> l.stream()
.sorted(Comparator.comparing(Laptop::getPrice).reversed())
.collect(Collectors.toList())
))
);
So the results are like below:
[{"MSI", [2200, 1100, 900]},
{"HP", [3200, 900, 800]},
{"Dell", [2500, 2000, 700]}]
Then, I use the code in the bottom of the question, to create a Laptop list with the following contents:
[{"HP", 3200}, {"Dell", 2500}, {"MSI", 2200},
{"Dell", 2000}, {"MSI", 1100}, {"HP", 900},
{"MSI", 900}, {"HP", 800}, {"Dell", 700}]
So basically, I iterate the map and from each key, I extract the next in line element of the list.
do {
for (Map.Entry<String, List<Laptop>> entry :
laptopsMap.entrySet()) {
String key = entry.getKey();
List<Laptop> value = entry.getValue();
finalResultsList.add(value.get(0));
value.remove(0);
if (value.size() == 0) {
laptopsMap.entrySet()
.removeIf(pr -> pr.getKey().equals(key));
} else {
laptopsMap.replace(key, value);
}
}
} while(!laptopsMap.isEmpty());
I instead of all this in-class code need to use a mongoTemplate database argument, but I cant seem to figure out how to create such a complex query. I have read material about Aggregation but I have not found anything helpful enough. At the moment, I have started putting a query together as shown below:
Query query = new Query();
query.limit(numOfLaptops);
query.addCriteria(Criteria.where(Laptop.PRICE).gte(minPrice));
I am stuck with the below requirement and not sure how can I proceed with it:
I have a function like:
public void compareExcel(Map<Object,List<HashMap>>) compareMaps){}
This function will take a map as an input parameter. This map will contain the sheet name vs Sheet values(Column name - column values) mapping.
Basically the function input parameters will be like:
<Excel1,(scenario:10)
(timing: 20)
Excel2,(scenario:30)
(timing: 40)
Excel3,(scenario:50)
(timing: 60)
>
Here my excel1 having two columns(scenario and timings) and having values as 10 and 20 respectively.
In the result, I will be needing the comparison like:
Map>
<scenario, <excel1,10>
<excel2,30>
<excel3,50>
timing, <excel1,20>
<excel2,40>
<excel3,60>
>
Any help will be appreciated.
Create/initialize the details of you output data-structure
LOOP (over the excelName:List pairs in you input)
LOOP (over the List that is the value in the pair)
//Each entry in the list is a map
Get the key-name (e.g. "scenario")
Get the value (e.g. "10")
//You already know the out key (i.e the excelName)
With the three known values, build/add to your output data-structure
On mobile so I can't even check syntax, but...
Map recopilation = new HashMap();
for(Object sheetName : compareMaps.keySet()) {
Map sheet = compareMaps.get(sheetName);
for (Object columnName : sheet.keySet()) {
if (recopilation.get(columnName) == null) {
recopilation.put(columnName, new HashMap());
}
((Map) recopilation.get(columnName)).put(sheetName, sheet.get(columnName));
}
}
Something like that. If it works, you should really throw some generics in there, I didn't mostly to save some typing.
I am not a java developer, and this is not my homework or something. I am just in need of getting the values of these parameters: end & begin. this is what I have:
rs = [{}, {end=2013/11/5, begin=2012/11/6}]
I am wonder if I could get values like this:
rs[1].end
rs[1].begin
the source is:
protected QueryParameters prepareForm(final ActionContext context) {
final SearchErrorLogForm form = context.getForm();
Map<String, Object> rs = form.getValues();
System.out.println(rs);
/*the output is: {pageParameters={}, period={end=2013/11/5, begin=2013/11/6}} */
}
sorry, the rs type is hashmap.
That is not a valid statement.
A proper way of assigning an array would be:
String dates[] = {"2013/11/5","2012/11/6"};
String start = dates[0];
String end = dates[1];
There is a excellent tutourial at oracle docs
Okay, that is a Map containing two Maps as it seems. The first map named "pageParameters" is empty. The second one is named period and contains two items. The key "end" maps to the value "2013/11/5". The key "begin" maps to the value "2013/11/6".
To access the objects in the map you could do like this:
final Map<String, String> period = (Map<String, String>) rs.get("period");
final String begin = period.get("begin");
final String end = period.get("end");
If you would like to change a value in the map period you will need to overwrite the already existing one:
period.put("end", "NEW_END");
rs.put("period", period);
For further information, Oracle has great tutorials on Hashmaps.
you can do like following:
rs[1][0] for the first
rs[1][rs[1].length-1] for the last
Below is data from 2 linkedHashMaps:
valueMap: { y=9.0, c=2.0, m=3.0, x=2.0}
formulaMap: { y=null, ==null, m=null, *=null, x=null, +=null, c=null, -=null, (=null, )=null, /=null}
What I want to do is input the the values from the first map into the corresponding positions in the second map. Both maps take String,Double as parameters.
Here is my attempt so far:
for(Map.Entry<String,Double> entryNumber: valueMap.entrySet()){
double doubleOfValueMap = entryNumber.getValue();
for(String StringFromValueMap: strArray){
for(Map.Entry<String,Double> entryFormula: formulaMap.entrySet()){
String StringFromFormulaMap = entryFormula.toString();
if(StringFromFormulaMap.contains(StringFromValueMap)){
entryFormula.setValue(doubleOfValueMap);
}
}
}
}
The problem with doing this is that it will set all of the values i.e. y,m,x,c to the value of the last double. Iterating through the values won't work either as the values are normally in a different order those in the formulaMap. Ideally what I need is to say is if the string in formulaMap is the same as the string in valueMap, set the value in formulaMap to the same value as in valueMap.
Let me know if you have any ideas as to what I can do?
This is quite simple:
formulaMap.putAll(valueMap);
If your value map contains key which are not contained in formulaMap, and you don't want to alter the original, do:
final Map<String, Double> map = new LinkedHashMap<String, Double>(valueMap);
map.keySet().retainAll(formulaMap.keySet());
formulaMap.putAll(map);
Edit due to comment It appears the problem was not at all what I thought, so here goes:
// The result map
for (final String key: formulaMap.keySet()) {
map.put(formulaMap.get(key), valueMap.get(key));
// Either return the new map, or do:
valueMap.clear();
valueMap.putAll(map);
for(Map.Entry<String,Double> valueFormula: valueMap.entrySet()){
formulaMap.put(valueFormula.getKey(), valueFormula.value());
}