Related
Thanks to the great help from Tenfour04, I've got wonderful code for handling CSV files.
However, I am in trouble like followings.
How to call these functions?
How to initialize 2-dimensional array variables?
Below is the code that finally worked.
MainActivity.kt
package com.surlofia.csv_tenfour04_1
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import java.io.File
import java.io.IOException
import com.surlofia.csv_tenfour04_1.databinding.ActivityMainBinding
var chk_Q_Num: MutableList<Int> = mutableListOf (
0,
1, 2, 3, 4, 5,
6, 7, 8, 9, 10,
11, 12, 13, 14, 15,
16, 17, 18, 19, 20,
)
var chk_Q_State: MutableList<String> = mutableListOf (
"z",
"a", "b", "c", "d", "e",
"f", "g", "h", "i", "j"
)
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// setContentView(R.layout.activity_main)
binding = ActivityMainBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
// Load saved data at game startup. It will be invalid if performed by other activities.
val filePath = filesDir.path + "/chk_Q.csv"
val file = File(filePath)
binding.fileExists.text = isFileExists(file).toString()
if (isFileExists(file)) {
val csvIN = file.readAsCSV()
for (i in 0 .. 10) {
chk_Q_Num[i] = csvIN[i][0].toInt()
chk_Q_State[i] = csvIN[i][1]
}
}
// Game Program Run
val csvOUT = mutableListOf(
mutableListOf("0","OK"),
mutableListOf("1","OK"),
mutableListOf("2","OK"),
mutableListOf("3","Not yet"),
mutableListOf("4","Not yet"),
mutableListOf("5","Not yet"),
mutableListOf("6","Not yet"),
mutableListOf("7","Not yet"),
mutableListOf("8","Not yet"),
mutableListOf("9","Not yet"),
mutableListOf("10","Not yet")
)
var tempString = ""
for (i in 0 .. 10) {
csvOUT[i][0] = chk_Q_Num[i].toString()
csvOUT[i][1] = "OK"
tempString = tempString + csvOUT[i][0] + "-->" + csvOUT[i][1] + "\n"
}
binding.readFile.text = tempString
// and save Data
file.writeAsCSV(csvOUT)
}
// https://www.techiedelight.com/ja/check-if-a-file-exists-in-kotlin/
private fun isFileExists(file: File): Boolean {
return file.exists() && !file.isDirectory
}
#Throws(IOException::class)
fun File.readAsCSV(): List<List<String>> {
val splitLines = mutableListOf<List<String>>()
forEachLine {
splitLines += it.split(", ")
}
return splitLines
}
#Throws(IOException::class)
fun File.writeAsCSV(values: List<List<String>>) {
val csv = values.joinToString("\n") { line -> line.joinToString(", ") }
writeText(csv)
}
}
chk_Q.csv
0,0
1,OK
2,OK
3,Not yet
4,Not yet
5,Not yet
6,Not yet
7,Not yet
8,Not yet
9,Not yet
10,Not yet
1. How to call these functions?
The code below seems work well.
Did I call these funtions in right way?
Or are there better ways to achieve this?
read
if (isFileExists(file)) {
val csvIN = file.readAsCSV()
for (i in 0 .. 10) {
chk_Q_Num[i] = csvIN[i][0].toInt()
chk_Q_State[i] = csvIN[i][1]
}
}
write
file.writeAsCSV(csvOUT)
2. How to initialize 2-dimensional array variables?
val csvOUT = mutableListOf(
mutableListOf("0","OK"),
mutableListOf("1","OK"),
mutableListOf("2","OK"),
mutableListOf("3","Not yet"),
mutableListOf("4","Not yet"),
mutableListOf("5","Not yet"),
mutableListOf("6","Not yet"),
mutableListOf("7","Not yet"),
mutableListOf("8","Not yet"),
mutableListOf("9","Not yet"),
mutableListOf("10","Not yet")
)
I would like to know the clever way to use a for loop instead of writing specific values one by one.
For example, something like bellow.
val csvOUT = mutableListOf(mutableListOf())
for (i in 0 .. 10) {
csvOUT[i][0] = i
csvOUT[i][1] = "OK"
}
But this gave me the following error message:
Not enough information to infer type variable T
It would be great if you could provide an example of how to execute this for beginners.
----- Added on June 15, 2022. -----
[Question 1]
Regarding initialization, I got an error "keep stopping" when I executed the following code.
The application is forced to terminate.
Why is this?
val csvOUT: MutableList<MutableList<String>> = mutableListOf(mutableListOf())
for (i in 0 .. 10) {
csvOUT[i][0] = "$i"
csvOUT[i][1] = "OK"
}
[Error Message]
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.surlofia.csv_endzeit_01/com.surlofia.csv_endzeit_01.MainActivity}: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
In my opinion there are basically two parts to your question. First you need an understanding of the Kotlin type system including generics. Secondly you want some knowledge about approaches to the problem at hand.
type-system and generics
The function mutableListOf you're using is generic and thus needs a single type parameter T, as can be seen by definition its taken from the documentation:
fun <T> mutableListOf(): MutableList<T>
Most of the time the Kotlin compiler is quite good at type-inference, that is guessing the type used based on the context. For example, I do not need to provide a type explicitly in the following example, because the Kotlin compiler can infer the type from the usage context.
val listWithInts = mutableListOf(3, 7)
The infered type is MutableList<Int>.
However, sometimes this might not be what one desires. For example, I might want to allow null values in my list above. To achieve this, I have to tell the compiler that it should not only allow Int values to the list but also null values, widening the type from Int to Int?. I can achieve this in at least two ways.
providing a generic type parameter
val listWithNullableInts = mutableListOf<Int?>(3, 7)
defining the expected return type explicitly
val listWithNullableInts: MutableList<Int?> = mutableListOf(3, 7)
In your case the compiler does NOT have enough information to infer the type from the usage context. Thus you either have to provide it that context, e.g. by passing values of a specific type to the function or using one of the two options named above.
initialization of multidimensional arrays
There are questions and answers on creating multi-dimensional arrays in Kotlin on StackOverflow already.
One solution to your problem at hand might be the following.
val csvOUT: MutableList<MutableList<String>> = mutableListOf(mutableListOf())
for (i in 0 .. 10) {
csvOUT[i][0] = "$i"
csvOUT[i][1] = "OK"
}
You help the Kotlin compiler by defining the expected return type explicitly and then add the values as Strings to your 2D list.
If the dimensions are fixed, you might want to use fixed-size Arrays instead.
val csvArray = Array(11) { index -> arrayOf("$index", "OK") }
In both solutions you convert the Int index to a String however.
If the only information you want to store for each level is a String, you might as well use a simple List<String and use the index of each entry as the level number, e.g.:
val csvOut = List(11) { "OK" }
val levelThree = csvOut[2] // first index of List is 0
This would also work with more complicated data structures instead of Strings. You simply would have to adjust your fun File.writeAsCSV(values: List<List<String>>) to accept a different type as the values parameter.
Assume a simple data class you might end up with something along the lines of:
data class LevelState(val state: String, val timeBeaten: Instant?)
val levelState = List(11) { LevelState("OK", Instant.now()) }
fun File.writeAsCSV(values: List<LevelState>) {
val csvString = values
.mapIndexed { index, levelState -> "$index, ${levelState.state}, ${levelState.timeBeaten}" }
.joinToString("\n")
writeText(csvString)
}
If you prefer a more "classical" imperative approach, you can populate your 2-dimensional Array / List using a loop like for in.
val list: MutableList<MutableList<String>> = mutableListOf() // list is now []
for (i in 0..10) {
val innerList: MutableList<String> = mutableListOf()
innerList.add("$i")
innerList.add("OK")
innerList.add("${Instant.now()}")
list.add(innerList)
// list is after first iteration [ ["0", "OK", "2022-06-15T07:03:14.315Z"] ]
}
The syntax listName[index] = value is just syntactic sugar for the operator overload of the set operator, see the documentation on MutableList for example.
You cannot access an index, that has not been populated before, e.g. during the List's initialization or by using add; or else you're greeted with a IndexOutOfBoundsException.
If you want to use the set operator, one option is to use a pre-populated Array as such:
val array: Array<Array<String>>> = Array(11) {
Array(3) { "default" }
} // array is [ ["default, "default", "default"], ...]
array[1][2] = "myValue"
However, I wouldn't recommend this approach, as it might lead to left over, potentially invalid initial data, in case one misses to replace a value.
this is my second try to explain a bit more precisely what I'm looking for ;-)
I set a webhook in Mailchimp that fires every time a new subscriber of an audience appears. Mailchimp sends a HTTP POST request to a Jira Sriptrunner REST endpoint.
The content type of this request is application/x-www-form-urlencoded.
Within the Jira endpoint I would like to read the request data. How can I do that?
The payload (raw body) I receive looks like this:
type=unsubscribe&fired_at=2020-05-26+07%3A04%3A42&data%5Baction%5D=unsub&data%5Breason%5D=manual&data%5Bid%5D=34f28a4516&data%5Bemail%5D=examlple%40bla.com&data%5Bemail_type%5D=html&data%5Bip_opt%5D=xx.xxx.xxx.198&data%5Bweb_id%5D=118321378&data%5Bmerges%5D%5BEMAIL%5D=example%40bla.com&data%5Bmerges%5D%5BFNAME%5D=Horst&data%5Bmerges%5D%5BLNAME%5D=Schlemmer&data%5Bmerges%5D%5BCOMPANY%5D=First&data%5Bmerges%5D%5BADDRESS%5D%5Baddr1%5D=XXX
Now I would like to parse the data of the raw body into a JSON or something similiar.
The result might look like this:
{
"web_id": 123,
"email": "example#bla.com",
"company": "First",
...
}
Meanwhile I searched around a little and found something like the node.js "querystring" module. It would be great if there is something similiar within Groovy or any other way to parse the data of application/x-www-form-urlencoded to json format.
Best regards and thanks in advance
Bernhard
def body = "type=unsubscribe&fired_at=2020-05-26+07%3A04%3A42&data%5Baction%5D=unsub&data%5Breason%5D=manual&data%5Bid%5D=34f28a4516&data%5Bemail%5D=examlple%40bla.com&data%5Bemail_type%5D=html&data%5Bip_opt%5D=xx.xxx.xxx.198&data%5Bweb_id%5D=118321378&data%5Bmerges%5D%5BEMAIL%5D=example%40bla.com&data%5Bmerges%5D%5BFNAME%5D=Horst&data%5Bmerges%5D%5BLNAME%5D=Schlemmer&data%5Bmerges%5D%5BCOMPANY%5D=First&data%5Bmerges%5D%5BADDRESS%5D%5Baddr1%5D=XXX"
def map = body.split('&').collectEntries{e->
e.split('=').collect{ URLDecoder.decode(it, "UTF-8") }
}
assert map.'data[merges][EMAIL]'=='example#bla.com'
map.each{println it}
prints:
type=unsubscribe
fired_at=2020-05-26 07:04:42
data[action]=unsub
data[reason]=manual
data[id]=34f28a4516
data[email]=examlple#bla.com
data[email_type]=html
data[ip_opt]=xx.xxx.xxx.198
data[web_id]=118321378
data[merges][EMAIL]=example#bla.com
data[merges][FNAME]=Horst
data[merges][LNAME]=Schlemmer
data[merges][COMPANY]=First
data[merges][ADDRESS][addr1]=XXX
A imple no-brainer groovy:
def a = '''
data[email_type]: html
data[web_id]: 123
fired_at: 2020-05-26 07:28:25
data[email]: example#bla.com
data[merges][COMPANY]: First
data[merges][FNAME]: Horst
data[ip_opt]: xx.xxx.xxx.xxx
data[merges][PHONE]: xxxxx
data[merges][ADDRESS][zip]: 33615
type: subscribe
data[list_id]: xxXXyyXX
data[merges][ADDRESS][addr1]: xxx.xxx'''
def res = [:]
a.eachLine{
def parts = it.split( /\s*:\s*/, 2 )
if( 2 != parts.size() ) return
def ( k, v ) = parts
def complexKey = ( k =~ /\[(\w+)\]/ ).findAll()
if( complexKey ) complexKey = complexKey.last().last()
res[ ( complexKey ?: k ).toLowerCase() ] = v
}
res
gives:
[email_type:html, web_id:123, fired_at:2020-05-26 07:28:25,
email:example#bla.com, company:First, fname:Horst, ip_opt:xx.xxx.xxx.xxx,
phone:xxxxx, zip:33615, type:subscribe, list_id:xxXXyyXX, addr1:xxx.xxx]
I found a solution finally. I hope you understand and maybe it helps others too ;-)
Starting from daggett's answer I did the following:
// Split body and remove unnecessary characters
def map = body.split('&').collectEntries{e->
e.split('=').collect{ URLDecoder.decode(it, "UTF-8") }
}
// Processing the map to readable stuff
def prettyMap = new JsonBuilder(map).toPrettyString()
// Convert the pretty map into a json object
def slurper = new JsonSlurper()
def jsonObject = slurper.parseText(prettyMap)
(The map looks pretty much like in daggett's answer.
prettyMap)
Then I extract the keys:
// Finally extracting customer data
def type = jsonObject['type']
And I get the data I need. For example
Type : subscribe
...
First Name : Heinz
...
Thanks to daggett!
What I want to do:
Get user input from HTML form, store input in variables within Django and perform calculations with variables.
To accomplish that, I use following code:
my_var = requst.POST.get('my_var')
To prevent having 'None' stored in 'my_var' when a Django page is first rendered, I usually use
if my_var == None:
my_var = 1
To keep it simple when using a bunch of variables I came up with following idea:
I store all variable names in a list
I loop through list and create a dictionary with variable names as key and user input as value
For that I wrote this code in python which works great:
list_eCar_properties = [
'car_manufacturer',
'car_model',
'car_consumption',]
dict_sample_eCar = {
'car_manufacturer' : "Supr-Duper",
'car_model' : "Lightning 1000",
'car_consumption' : 15.8,
}
dict_user_eCar = {
}
my_dict = {
'car_manufacturer' : None,
'car_model' : None,
'car_consumption' : None,
}
for item in list_eCar_properties:
if my_dict[item] == None:
dict_user_eCar[item] = dict_sample_eCar[item]
else:
dict_user_eCar[item] = my_dict[item]
print(dict_user_eCar)
Works great - when I run the code, a dictionary (dict_user_eCar) is created where user input (in this case None simulated by using a second dictionary my_dict) is stored. When User leaves input blank - Data from dict_sample_eCar is used.
Now, when I transfer that code to my Django view things don't work not as nice anymore. Code as follows:
def Verbrauchsrechner_eAuto(request):
list_eCar_properties = [
'car_manufacturer',
'car_model',
'car_consumption',
]
dict_model_eCar = {
'car_manufacturer' : "Supr-Duper",
'car_model' : "Lightning 1000",
'car_consumption' : 15.8,
}
dict_user_eCar = {
}
for item in list_eCar_properties:
dict_user_eCar[item] = dict_model_eCar[item]
context = {
'dict_user_eCar' : dict_user_eCar,
'dict_model_eCar' : dict_model_eCar,
'list_eCar_properties' : list_eCar_properties,
}
return render(request, 'eAuto/Verbrauchsrechner_eAuto.html', context = context)
Result: The page gets rendered with only the first dictionary entry. All others are left out. In this cases only car_manufacturer gets rendered to html-page.
Sorry folks - as I was reviewing my post, I realized, that I had a major srew-up at the last part's indentation:
context and return both were part of the for-loop which obviously resulted in a page-rendering after the first loop.
I corrected the code as follows:
for item in list_eCar_properties:
dict_user_eCar[item] = dict_model_eCar[item]
context = {
'dict_user_eCar' : dict_user_eCar,
'dict_model_eCar' : dict_model_eCar,
'list_eCar_properties' : list_eCar_properties,
}
return render(request, 'eAuto/Verbrauchsrechner_eAuto.html', context = context)`
Since I didn't want the time I spend to write this post to be wasted - I simply posted it anyway - even though I found the mistake myself.
Lessons learned for a Newbie in programming:
To many comments in your own code might result in a big confusion
Try to be precise and keep code neat and tidy
Do 1 and 2 before writing long posts in stackoverflow
Maybe someone else will benefit from this.
I'm trying to use a PCRE regular expression to extract some JSON. I'm using a version of MariaDB which does not have JSON functions but does have REGEX functions.
My string is:
{"device_types":["smartphone"],"isps":["a","B"],"network_types":[],"countries":[],"category":["Jebb","Bush"],"carriers":[],"exclude_carriers":[]}
I want to grab the contents of category. I'd like a matching group that contains 2 items, Jebb and Bush (or however many items are in the array).
I've tried this pattern but it only matches the first occurrence: /(?<=category":\[).([^"]*).*?(?=\])/g
Does this match your needs? It should match the category array regardless of its size.
"category":(\[.*?\])
regex101 example
JSON not a regular language. Since it allows arbitrary embedding of balanced delimiters, it must be at least context-free.
For example, consider an array of arrays of arrays:
[ [ [ 1, 2], [2, 3] ] , [ [ 3, 4], [ 4, 5] ] ]
Clearly you couldn't parse that with true regular expressions.
See This Topic:
Regex for parsing single key: values out of JSON in Javascript
Maybe Helpful for you.
Using a set of non-capturing group you can extract a predefined json array
regex answer: (?:\"category\":)(?:\[)(.*)(?:\"\])
That expression extract "category":["Jebb","Bush"], so access the first group
to extract the array, sample java code:
Pattern pattern = Pattern.compile("(?:\"category\":)(?:\\[)(.*)(?:\"\\])");
String body = "{\"device_types\":[\"smartphone\"],\"isps\":[\"a\",\"B\"],\"network_types\":[],\"countries\":[],\"category\":[\"Jebb\",\"Bush\"],\"carriers\":[],\"exclude_carriers\":[]}";
Matcher matcher = pattern.matcher(body);
assertThat(matcher.find(), is(true));
String[] categories = matcher.group(1).replaceAll("\"","").split(",");
assertThat(categories.length, is(2));
assertThat(categories[0], is("Jebb"));
assertThat(categories[1], is("Bush"));
There are many ways. One sloppy way to do it is /([A-Z])\w+/g
Please try it on your console like
var data = '{"device_types":["smartphone"],"isps":["a","B"],"network_types":[],"countries":[],"category":["Jebb","Bush"],"carriers":[],"exclude_carriers":[]}',
res = [];
data.match(/([A-Z])\w+/g); // ["Jebb", "Bush"]
OK the above was pretty sloppy however a solid single regex solution to extract every single element regardless of the number, one by one and to place them in an array (res) is the following...
var rex = /[",]+(\w*)(?=[",\w]*"],"carriers)/g,
str = '{"device_types":["smartphone"],"isps":["a","B"],"network_types":[],"countries":[],"category":["Jebb","Bush","Donald","Trump"],"carriers":[],"exclude_carriers":[]}',
arr = [],
res = [];
while ((arr = rex.exec(str)) !== null) {
res.push(arr[1]); // <- ["Jebb", "Bush", "Donald", "Trump"]
}
Check it out # http://regexr.com/3d4ee
OK lets do it. I have come up with a devilish idea. If JS had look-behinds this could have been done simply by reversing the applied logic in the previous example where i had used a look-forward. Alas, there aren't... So i decided to turn the world the other way around. Check this out.
String.prototype.reverse = function(){
return this.split("").reverse().join("");
};
var rex = /[",]+(\w*)(?=[",\w]*"\[:"yrogetac)/g,
str = '{"device_types":["smartphone"],"isps":["a","B"],"network_types":[],"countries":[],"category":["Jebb","Bush","Donald","Trump"],"carriers":[],"exclude_carriers":[]}',
rev = str.reverse();
arr = [],
res = [];
while ((arr = rex.exec(rev)) !== null) {
res.push(arr[1].reverse()); // <- ["Trump", "Donald", "Bush", "Jebb"]
}
res.reverse(); // <- ["Jebb", "Bush", "Donald", "Trump"]
Just use your console to confirm.
In c++ you can do it like this
bool foundmatch = false;
try {
std::regex re("\"([a-zA-Z]+)\"*.:*.\\[[^\\]\r\n]+\\]");
foundmatch = std::regex_search(subject, re);
} catch (std::regex_error& e) {
// Syntax error in the regular expression
}
If the number of items in the array is limited (and manageable), you could define it with a finite number of optional items. Like this one with a maximum of 5 items:
"category":\["([^"]*)"(?:,"([^"]*)"(?:,"([^"]*)"(?:,"([^"]*)"(?:,"([^"]*)")?)?)?)?
regex101 example here.
Regards.
I'm using code from https://github.com/alexholmes/json-mapreduce to read a multi-line json file into an RDD.
var data = sc.newAPIHadoopFile(
filepath,
classOf[MultiLineJsonInputFormat],
classOf[LongWritable],
classOf[Text],
conf)
I printed out the first n elements to check if it was working correctly.
data.take(n).foreach { p =>
val (line, json) = p
println
println(new JSONObject(json.toString).toString(4))
}
However when I try to look at the data, the arrays returned from take don't seem to be correct.
Instead of returning an array of the form
[ data[0], data[1], ... data[n] ]
it is in the form
[ data[n], data[n], ... data[n] ]
Is this an issue with the RDD I've created, or an issue with how I'm trying to print it?
I figured out why take it was returning an array with duplicate values.
As the API mentions:
Note: Because Hadoop's RecordReader class re-uses the same Writable object
for each record, directly caching the returned RDD will create many
references to the same object. If you plan to directly cache Hadoop
writable objects, you should first copy them using a map function.
Therefore in my case it was reusing the same LongWritable and Text objects. For example if I did:
val foo = data.take(5)
foo.map( r => System.identityHashCode(r._1) )
The output was:
Array[Int] = Array(1805824193, 1805824193, 1805824193, 1805824193, 1805824193)
So in order to prevent it from doing this, I simply mapped the reused objects to their respective values:
val data = sc.newAPIHadoopFile(
filepath,
classOf[MultiLineJsonInputFormat],
classOf[LongWritable],
classOf[Text],
conf ).map(p => (p._1.get, p._2.toString))