Regular Expression - Picking all instances of a string enclosed by parenthesis

Tag: java,regex

I'm currently working on a project where I am creating a parser for arithmetic expressions. I want to add some 'high end' functionality, but have an issue tied to regular expressions. I am relatively new to regular expressions, so I am not 100% certain its the right tool for this below case.

The aim is to have our users create an equation string for a calculation field (assisted by a GUI interface, so they don't have to format the string raw) that will then sit as a new field against our data presentation model for information we are storing in a CSV format in our database. However, I would like the user to be able to draw named fields from their data model into their calculations.

As an example, take the below example model.

Name (string - raw data - column 1)
Temp_in_degrees (number - raw data - column 2)
Speed (number - raw data column 3)

Say we want to add a new field to it, for temperature in Fahrenheit

Name (string - raw data - column 1)
Temp_in_degrees (number - raw data - column 2)
Speed (number - raw data column 3)
Temp_in_fahrenheit (number - calculated)

I have the string of the equation for field 4 as below. Notice it is referring to the value of field 2 in the raw data as part of the equation, enclosed in the parenthesis.

(({Temp_in_degrees} * 9) / 5) + 32

This is a very simple sample equation. Examples of higher complexity may include more than one reference to existing raw data fields.

Now, I would like to use regular expressions to look at a string like this, and to return all sub-strings within that string that happen to appear between the "{" and the "}". In our first example equation above, I would like to return Temp_in_degrees. In a much more complex (but nonsense) example:

({Temp_in_degrees} / {Speed}) * 30;

I would like to return Temp_in_degrees and Speed (or, loop through and handle each string as it is found)

Because of the users ability to customise their models, I cannot assume we are always going to have strings of the same name.

I do have an alternate idea for solving this issue, where I use String.indexOf to resolve it by looping the string, getting indexes, getting substrings between those indexes, then substituting values from our raw data into the string and repeat, but feel this is something RegEx should be able to help with.

Any ideas?

Best How To :

If you are planning to go with regular expressions, then the following might help:

try the following:

    String input = "({Temp_in_degrees} / {Speed}) * 30;";
    Pattern pattern = Pattern.compile("\\{\\S+\\}");

    Scanner scanner = new Scanner(input);
    String output;
    while ((output = scanner.findInLine(pattern)) != null) {
        System.out.println(output);
    }
    scanner.close();

Get current latitude and longitude android

java,android,gps,geolocation,location

See my post at http://gabesechansoftware.com/location-tracking/. The code you're using is just broken. It should never be used. The behavior you're seeing is one of the bugs- it doesn't handle the case of getLastLocation returning null, an expected failure. It was written by someone who kind of knew what he was...

Unfortunately, (My app) has stopped. Eclipse Android [duplicate]

java,android,eclipse,adt

In your MainActivity.java at line no 34 you are trying to initialize some widget that is not present in your xml layout which you have set it in your setContentView(R.layout.... That;s why you are geting nullpointerexception. EDIT: change your setContentView(R.layout.activity_main) to setContentView(R.layout.fragment_main)...

Join files using Apache Spark / Spark SQL

java,apache-spark,apache-spark-sql

If you use plain spark you can join two RDDs. let a = RDD<Tuple2<K,T>> let b = RDD<Tuple2<K,S>> RDD<Tuple2<K,Tuple2<S,T>>> c = a.join(b) This produces an RDD of every pair for key K. There are also leftOuterJoin, rightOuterJoin, and fullOuterJoin methods on RDD. So you have to map both datasets to...

error: cannot find symbol class AsyncCallWS Android

java,android,web-services

On the link you post, I see a class like below. Create this class in your project before using it. private class AsyncCallWS extends AsyncTask<String, Void, Void> { @Override protected Void doInBackground(String... params) { Log.i(TAG, "doInBackground"); getFahrenheit(celcius); return null; } @Override protected void onPostExecute(Void result) { Log.i(TAG, "onPostExecute"); tv.setText(fahren +...

Get network interfaces on remote machine

java,network-programming

No, we cannot by definition. The IP address is needed to hide the mac address from external world. To retrieve it you definitely need some code running on that machine. It means that you need some kind of agent. You can either implement it in Java or use platform specific...

How to check if an ExecutionResult is empty in Neo4j

java,neo4j

An execution result is essentially an iterator of a map, its type definition is something like: Iterable<Map<String,Object>> So you can easily just do: result.iterator().hasNext(); I think that its strictly a ResourceIterator, so if you get an iterator you are supposed to close it if you don't exhaust it. Check the...

type conversion if flex

java,actionscript-3,flex

You try to cast data type mx.collections:IList to UI component type spark.components:List, which of course leads to exception. Try to follow the error message hint and use mx.collections:IList: screenList.addAll(event.result as IList); ...

custom arraylist get distinct

java,android

It's not possible to do this using only the ArrayList. Either implement your own method which can be as simple as: private List<mystatistik> getAllUniqueEnemies(List<mystatistik> list){ List<mystatistik> uniqueList = new ArrayList<mystatistik>(); List<String> enemyIds = new ArrayList<String>(); for (mystatistik entry : list){ if (!enemyIds.contains(entry.getEnemyId())){ enemyIds.add(entry.getEnemyId()); uniqueList.add(entry); } } return uniqueList; } Or...

Reading and modifying the text from the text file in Java

java

I wrote a quick method for you that I think does what you want, i.e. remove all occurrences of a token in a line, where that token is embedded in the line and is identified by a leading dash. The method reads the file and writes it straight out to...

why java API prevents us to call add and remove together?

java,list,collections,listiterator

You're reading the wrong documentation: you should read ListIterator's javadoc. It says: Throws: ... IllegalStateException - if neither next nor previous have been called, or remove or add have been called after the last call to next or previous Now, if you want a reason, it's rather simple. You're playing...

Interpreting hex dump of java class file

java,class,hex

The 000000b0 is not part of the data. It's the memory address where the following 16 bytes are located. The two-digit hex numbers are the actual data. Read them from left to right. Each row is in two groups of eight, purely to asist in working out memory addresses etc....

Java Scanner not reading newLine after wrong input in datatype verification while loop

java,while-loop,java.util.scanner

You are reading too much from the scanner! In this line while (sc.nextLine() == "" || sc.nextLine().isEmpty()) you are basically reading a line from the scanner, comparing it (*) with "", then forgetting it, because you read the next line again. So if the first read line really contains the...

Can I install 2 or more Android SDK when using Eclipse

java,android,eclipse,sdk,versions

There shouldn't be any problem if you use the latest SDK version ; actually, this is recommended. However, make sure to set the correct "Target SDK", i.e. the highest android version you have successfully tested your app with, and the "Minimum Required SDK" as well....

How to write RegEx for inserting line break for line length more than 30 characters?

regex

Find what: ^(.{30}) Replace with: \1\n ...

PropertyNotFoundException in jsp

java,jsp

The name of your getter & setter is wrong. By convention it must be: public Integer getSurvey_id() { return survey_id; } public void setSurvey_id(Integer survey_id) { this.survey_id=survey_id; } ...

App Not Downloading Newest Version Of File [Java]

java,caching,download

Use URLConnection.setUseCaches(boolean);. In your case, it would be connection.setUseCaches(false);...

PHP Regular Expressions Counting starting consonants in a string

php,regex

This is one way to do it, using preg_match: $string ="SomeStringExample"; preg_match('/^[b-df-hj-np-tv-z]*/i', $string, $matches); $count = strlen($matches[0]); The regular expression matches zero or more (*) case-insensitive (/i) consonants [b-df-hj-np-tv-z] at the beginning (^) of the string and stores the matched content in the $matches array. Then it's just a matter...

Regex to remove `.` from a sub-string enclosed in square brackets

c#,.net,regex,string,replace

To remove all the dots present inside the square brackets. Regex.Replace(str, @"\.(?=[^\[\]]*\])", ""); DEMO To remove dot or ?. Regex.Replace(str, @"[.?](?=[^\[\]]*\])", ""); ...

Javadoc: Do parameter and return need an explicit type description

java,types,javadoc

No, there's no need, the JavaDoc tool parses the Java code and gets the types from there. This article on the Oracle Java site may be useful: How to Write Doc Comments for the Javadoc Tool From the @param part of that article: The @param tag is followed by the...

How to call MySQL view in Struts2 or Hibernate

java,mysql,hibernate,java-ee,struts2

You can simply create an Entity, that's mapping the database view: @Entity public class CustInfo { private String custMobile; private String profession; private String companyName; private Double annualIncome; } Make sure you include an @Id in your view as well, if that's an updatable view. Then you can simply use...

Reg ex matching a word

regex

You could use a negative lookahead which will exclude those having _FX following the initial alpha string ^ABD_DEF_GHIJ(?!_FX)(?:_\d{8})?$ see example here...

Form submit portlet with Spring MVC

java,jsp,spring-mvc,liferay,portlet

Which version of Liferay you are using? if it is > 6.2 GA1 Then in your liferay-portlet.xml file, please add this attribute and recompile and test again. <requires-namespaced-parameters>false</requires-namespaced-parameters> Liferay adds namespace to the request parameters by default. You need to disable it. ...

Android String if-statement

java,android,string

Correct me if I'm wrong. If you're saying that your code looks like this: new Thread(new Runnable() { public void run() { // thread code if (ready.equals("yes")) { // handler code } // more thread code }).start(); // later on... ready = "yes"; And you're asking why ready = "yes"...

how to call Java method which returns any List from R Language? [on hold]

java,r,rjava

You can do it with rJava package. install.packages('rJava') library(rJava) .jinit() jObj=.jnew("JClass") result=.jcall(jObj,"[D","method1") Here, JClass is a Java class that should be in your ClassPath environment variable, method1 is a static method of JClass that returns double[], [D is a JNI notation for a double array. See that blog entry for...

How can implement long running process in spring hibernate?

java,spring,hibernate

I recommend you to use DeferredResult of Spring. It´s a Future implementation, that use the http long poling technique. http://docs.spring.io/spring-framework/docs/3.2.0.BUILD-SNAPSHOT/api/org/springframework/web/context/request/async/DeferredResult.html So let´s says that you will make a request, and the server it will return you the deferredResult, and then your request will keep it open until the internal process(Hibernate)...

Get all prices with $ from string into an array in Javascript

javascript,regex,currency

It’s quite trivial: RegEx string.match(/\$((?:\d|\,)*\.?\d+)/g) || [] That || [] is for no matches: it gives an empty array rather than null. Matches $99 $.99 $9.99 $9,999 $9,999.99 Explanation / # Start RegEx \$ # $ (dollar sign) ( # Capturing group (this is what you’re looking for) (?: #...

Regular Expression for whole world

regex,c#-4.0,vb6

You can use: Public\s+Const\s+g(?<Name>[a-zA-Z][a-zA-Z0-9]*)\s+=\s+(?<Value>False|True) demo ...

match line break except line begin with spcific word or blank line

regex,notepad++

Try this regex: (?<=[a-zA-Z])(\n) I used parentheses to capture the newline character. https://regex101.com/r/zS9pB4/3...

Getting particular view from expandable listview

java,android,listview,android-fragments,expandablelistview

You shouldn't pass your view item form a fragment to an other. You should retrieve the object associated with your group view, pass this object to your second/edition fragment. You can use setTargetFragment(...) and onActivityResult(...) to send the modified text from your second to your first fragment. And then you...

Java dice roll with unexpected random number

java,if-statement

else { System.out.println(diceNumber); } You are printing the address of diceNumber by invoking its default toString() function in your else clause. That is why you are getting the [email protected] The more critical issue is why it gets to the 'else' clause, I believe that is not your intention. Note: In...

viewResolver with more folders inside of WEB-INF/jsp is not working in spring

java,spring,jsp,spring-mvc

Say you have a jsp test.jsp under /WEB-INF/jsp/reports From your controller return @RequestMapping("/helloWorld") public String helloWorld(Model model) { model.addAttribute("message", "Hello World!"); return "reports/test"; } ...

Get document on some condition in elastic search java API

java,elasticsearch,elasticsearch-plugin

When indexing documents in this form, Elasticsearch will not be able to parse those strings as dates correctly. In case you transformed those strings to correctly formatted timestamps, the only way you could perform the query you propose is to index those documents in this format { "start": "2010-09", "end":...

regex - Match filename with or without extension

regex,logstash-grok

This is about as simple as I can get it: \b\w+\.?\w* See demo...

Identify that a string could be a datetime object

python,regex,algorithm,python-2.7,datetime

What about fuzzyparsers: Sample inputs: jan 12, 2003 jan 5 2004-3-5 +34 -- 34 days in the future (relative to todays date) -4 -- 4 days in the past (relative to todays date) Example usage: >>> from fuzzyparsers import parse_date >>> parse_date('jun 17 2010') # my youngest son's birthday datetime.date(2010,...

Android Implicit Intent for Viewing a Video File

java,android,android-intent,uri,avd

Change your onClick method to below code. You should give the option to choose the external player. @Override public void onClick(View v) { Intent intent = new Intent(Intent.ACTION_VIEW); intent.setDataAndType(Uri.parse("https://youtu.be/jxoG_Y6dvU8"), "video/*"); startActivity(Intent.createChooser(intent, "Complete action using")); } ...

Get element starting with letter from List

java,android,list,indexof

The indexOf method doesn't accept a regex pattern. Instead you could do a method like this: public static int indexOfPattern(List<String> list, String regex) { Pattern pattern = Pattern.compile(regex); for (int i = 0; i < list.size(); i++) { String s = list.get(i); if (s != null && pattern.matcher(s).matches()) { return...

BitmapFont class does not have getBound(String) method

java,android,libgdx

After the API 1.5.6 we have a different way to get the String bound. try this GlyphLayout layout = new GlyphLayout(); layout.setText(bitmapFont,"text"); float width = layout.width; float height = layout.height; and it's not recommended to create new GlyphLayout on each frame, create once and use it. ...

Using world coordinates

java,libgdx

You shouldn't use constant a pixel-to-unit conversion, as this would lead to different behavior on different screen sizes/resolutions. Also don't forget about different aspect ratios, you also need to take care about them. The way you should solve this problem is using Viewports. Some of them support virtual screen sizes,...

How to do custom rounding of numbers in Java?

java,rounding

Math.floor(x+0.7) should do it. This should work for an arbitrary mantissa. Just add the offset to the next integer to your value and round down. The rounding is done by floor. Here is what the java API says to floor: Returns the largest (closest to positive infinity) double value that...

Android set clickable text to go one fragment to another fragment

java,android,android-fragments,spannablestring

If LoginActivity is a fragment class then it would be okay is you use setOnClickListener on textview. But for fragment change you have to change Intent to fragmentTransaction, Use something like, textview.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { getFragmentManager().beginTransaction().replace(R.id.container, new LoginActivity() ).addToBackStack("").commit(); }); But, if you want to...

Get the value of the last inserted record

java,jdbc

You may try this query: select stop_name from behaviour where created_at in (select max(created_at) from behaviour) ...

SOAP Client, Following an example

java,soap,saaj

Actually you can generate class with soap ui. And your program can easily call the service using the class created without construct your own request header and body But you need some library. Example java jdk comes with jax-ws lib tutorial: http://www.soapui.org/soap-and-wsdl/soap-code-generation.html...

How to block writes to standard output in java (System.out.println())

java,logging,stdout

If you can identify the thread you want to "mute" reliably somehow (e.g. by name), you can setOut to your own stream which will only delegate the calls to the actual System.out if they don't come from the muted thread.

Please can someone help me understand the exec method for regular expressions?

javascript,regex

I don't understand why it would give me two hellos back? Because the first entry in the array is the overall match for the expression, which is then followed by the content of any capture groups the expression defines. Since the expression defines one capture group, you get back...

Finding embeded xpaths in a String

java,regex

Use {} instead of () because {} are not used in XPath expressions and therefore you will not have confusions.

Logging operations in lightadmin

java,spring,logging,lightadmin

You can use the class AbstractRepositoryEventListener like it's show on the LightAdmin documentation here Add you logger insertion by overiding onAfterSave, onAfterCreate and onAfterDelete into your own RepositoryEventListener. After you just need to register your listener like this public class YourAdministration extends AdministrationConfiguration<YourObject> { public EntityMetadataConfigurationUnit configuration(EntityMetadataConfigurationUnitBuilder configurationBuilder) { return...

Get number from string

regex

Use \d+ to match one or more digits. \b(?:http:\/\/)?(?:www\.)?example\.com\/g\/(\d+)\/\w put http:// and www. inside a capturing or non-caturing group and then make it as optional by adding ? quantifier next to that group. For both http and https, it would be (?:https?:\/\/)? DEMO...

Selenium catch popup on close browser

java,selenium,browser

Instead of using driver.quit() to close the browser, closing it using the Actions object may work for you. This is another way to close the browser using the keyboard shortcuts. Actions act = new Actions(driver); act.sendKeys(Keys.chord(Keys.CONTROL+"w")).perform(); Or, if there are multiple tabs opened in driver window: act.sendKeys(Keys.chord(Keys.CONTROL,Keys.SHIFT+"w")).perform(); ...

Mysterious claim of a missing { in eclipse

java,eclipse

In Java, you cannot write executable statements directly in class.So this is syntactically wrong: for(int i=0; i<10; i++) { this.colorList[i] = this.allColors[this.r.nextInt(this.allColors.length)]; } Executable statements can only be in methods/constructors/code blocks...