Search Results

Search found 55248 results on 2210 pages for 'java memory model'.

Page 488/2210 | < Previous Page | 484 485 486 487 488 489 490 491 492 493 494 495  | Next Page >

  • Intelligent search and generation of Java code, preferrably using Python?

    - by Ipsquiggle
    Basically, I do lots of one-off code generation, large-scale refactorings, etc. etc. in Java. My tool language of choice is Python, but I'll take whatever solutions you can offer. Here is a simplified illustration of what I would like, in a pseudocode Generating an implementation for an interface search within my project: for each Interface as iName: write class(name=iName+"Impl", implements=iName) search within the body of iName: for each Method as mName: write method(name=mName, body="// TODO implement this...") Basically, the tool I'm searching for would allow me to: parse files according to their Java structure ("search for interfaces") search for words contextualized by language elements and types ("variables of type SomeClass", "doStuff() method calls on SomeClass instances") to run searches with structural context ("within the body of the current result") easily replace or generate code (with helpers to generate, as above, or functions for replacing, "rename the interface to Foo", "insert the line Blah.Blah()", etc.) The point is, I don't want to spend a lot of time writing these things, as they are usually throwaway. But sometimes I need something just a little smarter than what grep offers. It wouldn't be too hard to write up a simplistic version of this, but if I'm going to use something like this at all, I'd expect it to be robust. Any suggestions of a tool/library that will help me accomplish this?

    Read the article

  • Does anyone know of a good guide to configure GC in Java?

    - by evilpenguin
    I'm having trouble with a JVM running an app, whose heap memory looks like a comb. It's constantly jumping from 1.5 GB to 3 GB and slowly deteriorating to higher values. I'm using G1 GC algorithm, but have no idea how to configure it. I do not have access to the code of the app I'm running and, needless to say, it's a rather large app. So, bottom line, does anyone know of a good guide to configure GC in Java?

    Read the article

  • MidiSystem.getSequencer() returns Audio Device Unavailable

    - by ksemeks
    I've keep having an exception thrown, on and on. When i try to make a new Sequencer object, i keep getting the javax.sound.midi.MidiUnavailableException: Audio Device Unavailable exception. So, here's the code: import javax.sound.midi.*; public class MiniMusicPlayer1 { public static void main(String[] args) { try { Sequencer sequencer = MidiSystem.getSequencer(); sequencer.open(); Sequence seq = new Sequence(Sequence.PPQ, 4); Track track = seq.createTrack(); for (int i = 5; i < 61; i += 4) { track.add(makeEvent(144, 1, i, 100, i)); track.add(makeEvent(128, 1, i, 100, (i+2))); } sequencer.setSequence(seq); sequencer.setTempoInBPM(220); sequencer.start(); } catch (Exception e) { e.printStackTrace(); } } public static MidiEvent makeEvent(int comd, int chan, int one, int two, int tick) { MidiEvent event = null; try { ShortMessage a = new ShortMessage(); a.setMessage(comd, chan, one, two); event = new MidiEvent(a, tick); } catch (Exception e) { e.printStackTrace(); } return event; } } And here's the complete error (at compile): javax.sound.midi.MidiUnavailableException: Audio Device Unavailable at com.sun.media.sound.MixerSynth.implOpen(MixerSynth.java:165) at com.sun.media.sound.AbstractMidiDevice.doOpen(AbstractMidiDevice.java:144) at com.sun.media.sound.AbstractMidiDevice.openInternal(AbstractMidiDevice.java:134) at com.sun.media.sound.AbstractMidiDevice.getReceiverReferenceCounting(AbstractMidiDevice.java:339) at javax.sound.midi.MidiSystem.getReceiver(MidiSystem.java:243) at javax.sound.midi.MidiSystem.getSequencer(MidiSystem.java:442) at javax.sound.midi.MidiSystem.getSequencer(MidiSystem.java:348) at MiniMusicPlayer1.main(MiniMusicPlayer1.java:9) First i was unable to play MIDI files on my pc, but then i got it to work, so now i can play MIDI files, that's okay. I tried even to close every process which uses my sound card, but the error is still there. Anyone can help me?

    Read the article

  • How to access a subset of XML data in Java when the XML data is too large to fit in memory?

    - by Michael Jones
    What I would really like is a streaming API that works sort of like StAX, and sort of like DOM/JDom. It would be streaming in the sense that it would be very lazy and not read things in until needed. It would also be streaming in the sense that it would read everything forwards (but not backwards). Here's what code that used such an API would look like. URL url = ... XMLStream xml = XXXFactory(url.inputStream()) ; // process each <book> element in this document. // the <book> element may have subnodes. // You get a DOM/JDOM like tree rooted at the next <book>. while (xml.hasContent()) { XMLElement book = xml.getNextElement("book"); processBook(book); } Does anything like this exist?

    Read the article

  • Is there a nice way of having static generic parameters is Java?

    - by Chris
    Hello, recently I'm writing some functions that I take from Haskell and translate into Java. One of the main problems I have is I cannot easily create a static property with a generic type. Let me explain by a little example... // An interface to implement functions public interface Func<P, R> { public R apply(P p); } // What I want to do... (incorrect in Java) public class ... { public static <T> Func<T, T> identity = new Func<T, T>() { public T apply(T p) { return p; } } } // What I do right now public class ... { private static Func<Object, Object> identity = new Func<Object, Object>() { public Object apply(Object p) { return p; } } @SuppressWarnings("unchecked") public static <T> Func<T, T> getIdentity() { return (Func<T, T>)identity; } } Are there any easier ways to do something like that? What kind of problems might arise if the syntax I used would be valid?

    Read the article

  • declare decision structure inside of a System.out.println

    - by user2899249
    So I am working on an assignment where I have to have a print method in a constructor that displays a distance. I also have to have three separate get methods depending on what the input is in the demo class. My question is that I am trying to write the print method to contain a decision structure based on which get is used. public void prt() { DecimalFormat formatter = new DecimalFormat("#,##0.00"); System.out.println("The time it takes the sound to travel " + distance + " feet through air is " + if (getSpeedInAir() > 0) { formatter.format(getSpeedInAir()); } else if (getSpeedInWater() > 0) { formatter.format(getSpeedInWater()); } else if (getSpeedInSteel() > 0) { formatter.format(getSpeedInSteel()); } else "error";) } After trying to compile I am getting the following errors. Microsoft Windows [Version 6.1.7601] Copyright (c) 2009 Microsoft Corporation. All rights reserved. C:\Users\GlaDOS\Desktop\JavaStuffj Speed C:\Users\GlaDOS\Desktop\JavaStuffdel *.class C:\Users\GlaDOS\Desktop\JavaStuffjavac Speed.java Speed.java:43: error: illegal start of expression " feet through air is " + if (getSpeedInAir() 0) ^ Speed.java:43: error: ';' expected " feet through air is " + if (getSpeedInAir() 0) ^ Speed.java:43: error: not a statement " feet through air is " + if (getSpeedInAir() 0) ^ Speed.java:43: error: ';' expected " feet through air is " + if (getSpeedInAir() 0) ^ Speed.java:47: error: 'else' without 'if' else if (getSpeedInWater() > 0) ^ Speed.java:56: error: not a statement "error";) ^ Speed.java:56: error: illegal start of expression "error";) ^ 7 errors C:\Users\GlaDOS\Desktop\JavaStuffjava Speed Error: Could not find or load main class Speed Any help on why this is happening would be greatly appreciated.

    Read the article

  • Can a Java HashMap's size() be out of sync with its actual entries' size ?

    - by trix
    I have a Java HashMap called statusCountMap. Calling size() results in 30. But if I count the entries manually, it's 31 This is in one of my TestNG unit tests. These results below are from Eclipse's Display window (type code - highlight - hit Display Result of Evaluating Selected Text). statusCountMap.size() (int) 30 statusCountMap.keySet().size() (int) 30 statusCountMap.values().size() (int) 30 statusCountMap (java.util.HashMap) {40534-INACTIVE=2, 40526-INACTIVE=1, 40528-INACTIVE=1, 40492-INACTIVE=3, 40492-TOTAL=4, 40513-TOTAL=6, 40532-DRAFT=4, 40524-TOTAL=7, 40526-DRAFT=2, 40528-ACTIVE=1, 40524-DRAFT=2, 40515-ACTIVE=1, 40513-DRAFT=4, 40534-DRAFT=1, 40514-TOTAL=3, 40529-DRAFT=4, 40515-TOTAL=3, 40492-ACTIVE=1, 40528-TOTAL=4, 40514-DRAFT=2, 40526-TOTAL=3, 40524-INACTIVE=2, 40515-DRAFT=2, 40514-ACTIVE=1, 40534-TOTAL=3, 40513-ACTIVE=2, 40528-DRAFT=2, 40532-TOTAL=4, 40524-ACTIVE=3, 40529-ACTIVE=1, 40529-TOTAL=5} statusCountMap.entrySet().size() (int) 30 What gives ? Anyone has experienced this ? I'm pretty sure statusCountMap is not being modified at this point. There are 2 methods (lets call them methodA and methodB) that modify statusCountMap concurrently, by repeatedly calling incrementCountInMap. private void incrementCountInMap(Map map, Long id, String qualifier) { String key = id + "-" + qualifier; if (map.get(key) == null) { map.put(key, 0); } synchronized (map) { map.put(key, map.get(key).intValue() + 1); } } methodD is where I'm getting the issue. methodD has a TestNG @dependsOnMethods = { "methodA", "methodB" } so when methodD is executing, statusCountMap is pretty much static already. I'm mentioning this because it might be a bug in TestNG. I'm using Sun JDK 1.6.0_24. TestNG is testng-5.9-jdk15.jar Hmmm ... after rereading my post, could it be because of concurrent execution of outside-of-synchronized-block map.get(key) == null & map.put(key,0) that's causing this issue ?

    Read the article

  • how to transfer a time which was zero at year of 0000(maybe) to java.util.Date

    - by hguser
    I have a gps time in the database,and when I do some query,I have to use the java.util.Date,however I found that I do not know how to change the gps time to java.util.Date. Here is a example: The readable time === The GPS time 2010-11-15 13:10:00 === 634254192000000000 2010-11-15 14:10:00 === 634254228000000000 The period of the two date is "36000000000",,obviously it stands for one hour,so I think the unit of the gps time in the db must be nanosecond. 1 hour =3600 seconds= 3600*1000 milliseconds == 3600*1000*10000 nanoseconds Then I try to convert the gps time: Take the " 634254228000000000" as example,it stands for("2010-11-15 14:10:00"); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ssZ"); Date d = new Date(63425422800000L); System.out.println(sdf.format(d)); The result is 3979-11-15 13:00:00+0000. Of course it is wrong,then I try to calculate : 63425422800000/3600000/24/365=2011.xxx So it seems that the gps time here is not calcuated from Epoch(1970-01-01 00:00:00+0000). It maybe something like (0001-01-01 00:00:00+0000). Then I try to use the following method: Date date_0=sdf.parse("0001-01-01 00:00:00+0000"); Date d = new Date(63425422800000L); System.out.println(sdf.format(d.getTime() + date_0.getTime())); The result is: 2010-11-13 13:00:00+0000. :( Now I am confusing about how to calculate this gps time. Any suggestion?

    Read the article

  • implementing interface

    - by 1ace1
    hello guys so i have this assignment that i need to implement interface to go over an ArrayList and sort it (ascending or descnding).I dont want "the" answer i just need some suggestions on my approach and why i get this error Exception in thread "main" java.lang.ClassCastException: Week7.Check cannot be cast to java.lang.Comparable at java.util.Arrays.mergeSort(Unknown Source) at java.util.Arrays.sort(Unknown Source) at java.util.Collections.sort(Unknown Source) at Week7.TestCheck.main(TestCheck.java:18) This is how i did it: comparable had one method called public int compairTo(Object o) public class Check implements comparable { private Integer checkNumber; public Check(Integer newCheckNumber) { setCheckNumber(newCheckNumber); } public String toString() { return getCheckNumber().toString(); } public void setCheckNumber(Integer checkNumber) { this.checkNumber = checkNumber; } public Integer getCheckNumber() { return checkNumber; } @Override public int compairTo(Object o) { Check compair = (Check)o; int result = 0; if (this.getCheckNumber() > compair.getCheckNumber()) result = 1; else if(this.getCheckNumber() < compair.getCheckNumber()) result = -1; return result; } } in my main i had this import java.util.ArrayList; import java.util.Collections; public class TestCheck { public static void main(String[] args) { ArrayList checkList = new ArrayList(); checkList.add(new Check(445)); checkList.add(new Check(101)); checkList.add(new Check(110)); checkList.add(new Check(553)); checkList.add(new Check(123)); Collections.sort(checkList); for (int i =0; i < checkList.size(); i++){ System.out.println(checkList.get(i)); } } }

    Read the article

  • question about Ackermann function

    - by davit-datuashvili
    i am doing to write recursive program which calculates Ackemann function http://en.wikipedia.org/wiki/Ackermann_function here is code public class Ackermann{ public static long ackermann( long m,long n){ return (m==0)? n+1: (m>0 && n==0)? ackermann(m-1,1): (m>0 && n>0)? ackermann(m-1, ackermann(m,n-1)); } public static void main(String[]args){ long m=4; long n=2; System.out.println(ackermann(m,n)); } } but it shows me mistakes Ackermann.java:7: : expected (m>0 && n>0)? ackermann(m-1, ackermann(m,n-1)); ^ Ackermann.java:7: ';' expected (m>0 && n>0)? ackermann(m-1, ackermann(m,n-1)); ^ Ackermann.java:18: illegal start of expression public static void main(String[]args){ ^ Ackermann.java:18: ';' expected public static void main(String[]args){ ^ Ackermann.java:18: illegal start of expression public static void main(String[]args){ ^ Ackermann.java:18: ';' expected public static void main(String[]args){ ^ Ackermann.java:18: ';' expected public static void main(String[]args){ ^ Ackermann.java:26: reached end of file while parsing } ^ 8 errors please help

    Read the article

  • How can I measure the speed of code written in Java? (AI algorithms)

    - by Registered User
    Hi All, How can I measure the speed of code written in Java? I planning to develop software which will solve Sudoku using all presently available AI and ML algorithms and compare time against simple brute-force method. I need to measure time of each algorithm, I would like to ask for suggestions on what is the best way of doing that? Very important, program must be useful on any machine regardless to CPU power/memory. Thank you.

    Read the article

  • (Java) Get value of string loaded into dynamic-type object?

    - by Michael
    I'm very new to Java (~10 days), so my code is probably pretty bad, but here's what I've got: ArgsDataHolder argsData = new ArgsDataHolder(); // a class that holds two // ArrayList's where each element // representing key/value args Class thisArgClass; String thisArgString; Object thisArg; for(int i=2; i< argsString.length; i++) { thisToken = argsString[i]; thisArgClassString = getClassStringFromToken(thisToken).toLowerCase(); System.out.println("thisArgClassString: " + thisArgClassString); thisArgClass = getClassFromClassString(thisArgClassString); // find closing tag; concatenate middle Integer j = new Integer(i+1); thisArgString = getArgValue(argsString, j, "</" + thisArgClassString + ">"); thisArg = thisArgClass.newInstance(); thisArg = thisArgClass.valueOf(thisArgString); argsData.append(thisArg, thisArgClass); } The user basically has to input a set of key/value arguments into the command prompt in this format: <class>value</class>, e.g. <int>62</int>. Using this example, thisArgClass would be equal to Integer.class, thisArgString would be a string that read "62", and thisArg would be an instance of Integer that is equal to 62. I tried thisArg.valueOf(thisArgString), but I guess valueOf(<String>) is only a method of certain subclasses of Object. For whatever reason, I can't seem to be able to cast thisArg to thisArgClass (like so: thisArg = (thisArgClass)thisArgClass.newInstance();, at which point valueOf(<String>) should become accessible. There's got to be a nice, clean way of doing this, but it is beyond my abilities at this point. How can I get the value of the string loaded into a dynamically-typed object (Integer, Long, Float, Double, String, Character, Boolean, etc.)? Or am I just overthinking this, and Java will do the conversion for me? :confused:

    Read the article

  • byte and short data types in Java can accept the value outside the range by explicit cast. The higher data types however can not. Why?

    - by Lion
    Let's consider the following expressions in Java. byte a = 32; byte b = (byte) 250; int i = a + b; This is valid in Java even though the expression byte b = (byte) 250; is forced to assign the value 250 to b which is outside the range of the type byte. Therefore, b is assigned -6 and consequently i is assigned the value 26 through the statement int i = a + b;. The same thing is possible with short as follows. short s1=(short) 567889999; Although the specified value is outside the range of short, this statement is legal. The same thing is however wrong with higher data types such int, double, folat etc and hence, the following case is invalid and causes a compile-time error. int z=2147483648; This is illegal, since the range of int in Java is from -2,147,483,648 to 2147483647 which the above statement exceeds and issues a compile-time error. Why is such not wrong with byte and short data types in Java?

    Read the article

  • How to account for non-prime numbers 0 and 1 in java?

    - by shady
    I'm not sure if this is the right place to be asking this, but I've been searching for a solution for this on my own for quite some time, so hopefully I've come to the right place. When calculating prime numbers, the starting number that each number has to be divisible by is 2 to be a non-prime number. In my java program, I want to include all the non-prime numbers in the range from 0 to a certain number, so how do I include 0 and 1? Should I just have separate if and else-if statements for 0 and 1 that state that they are not prime numbers? I think that maybe 0 and 1 should be included in the java for loop, but I don't know how to go about doing that. for (int i = 2; i < num; i++){ if (num % i == 0){ System.out.println(i + " is not a prime number. "); } else{ System.out.println(i + " is a prime number. "); } }

    Read the article

  • How to get java singleton object manager to return any type of object?

    - by Robert
    I'm writing an interactive fiction game in java from scratch. I'm currently storing all of my game object references in a hashmap in a singleton called ObjectManager. ObjectManager has a function called get which takes an integer ID and returns the appropriate reference. The problem is that it returns a BaseObject when I need to return subclasses of BaseObject with more functionality. So, what I've done so far is I've added a getEntity function which returns BaseEntity (which is a subclass of BaseObject). However, when I need the function to return to an object that is a subclass of BaseEntity that has added, required functionality, I will need to make another function. I know there is a better way, but I don't know what it is. I know very little of design patterns, and I'm not sure which one to use here. I tried passing 'class' as a parameter, but that didn't get me anywhere. public BaseObject get(int ID){ return (BaseObject)refMap.get(ID); } public BaseEntity getEntity(int ID){ return (BaseEntity)refMap.get(ID); } Thanks, java ninjas!

    Read the article

  • How to check whether a default browser is opened in the operating system (Java)?

    - by stempel1984
    Hi, I am newbie here. During my work, I faced an interesting problem. I need to: check whether a default html browser is opened; check whether the browser is minimized/maximized (simply, a window's state); get an url address typed in the browser. If any of these conditions is not met, I have to open the browser in a maximized view with a desired url address. I primarily wanted to do all this in Java, but it came to my mind that I should employ many techniques/technologies and combine them appropriately to complete the functionality. But, which ones? That's the problem. I just recalled Windows API, but I'm not sure if it is of any help... Some users on another forum suggested that I should consider JNI (no experience at all)... I only know how to open a default browser (e.g. with use of the 'browse(URI uri)' method of the 'java.awt.Desktop' class) - that's too little to be proud of. Please give me some hints, maybe links to reasonable discussions, I would greatly appreciate any suggestions how to approach the problem.

    Read the article

  • Data caching in ASP.Net applications

    - by nikolaosk
    In this post I will continue my series of posts on caching. You can read my other post in Output caching here .You can read on how to cache a page depending on the user's browser language. Output caching has its place as a caching mechanism. But right now I will focus on data caching .The advantages of data caching are well known but I will highlight the main points. We have improvements in response times We have reduced database round trips We have different levels of caching and it is up to us...(read more)

    Read the article

  • Working with Temporal Data in SQL Server

    - by Dejan Sarka
    My third Pluralsight course, Working with Temporal Data in SQL Server, is published. I am really proud on the second part of the course, where I discuss optimization of temporal queries. This was a nearly impossible task for decades. First solutions appeared only lately. I present all together six solutions (and one more that is not a solution), and I invented four of them. http://pluralsight.com/training/Courses/TableOfContents/working-with-temporal-data-sql-server

    Read the article

  • The ethics of aggregating other peoples' content

    - by AaronBertrand
    Content theft Most of the recent - what I'll call - "discussions" about content aggregators have revolved around content theft. I'm not going to flip-flop on that topic: when you use someone else's work, you ask first, and if given the okay, you cite it. You can't take my blog article and post it on your site, implying that it is your own. Likewise, you shouldn't be taking a Books Online topic, changing three words and adding an intro sentence, and making that a blog post. I think this stuff is pretty...(read more)

    Read the article

  • PowerPivot and Parent/Child hierarchies

    - by AlbertoFerrari
    Does PowerPivot handle Parent/Child hierarchies? The common answer is “no”, since it does not handle them natively. During last PowerPivot course in London, I have been asked the same question once more and had an interesting discussion about this severe limitation of the PowerPivot data modeling and visualization capabilities. On my way back in Italy, I started thinking at a possible solution and, after some work, I managed to make PowerPivot handle Parent/Child hierarchies in a very nice way, which...(read more)

    Read the article

  • Storing large data in HTTP Session (Java Application)

    - by Umesh Awasthi
    I am asking this question in continuation with http-session-or-database-approach. I am planning to follow this approach. When user add product to cart, create a Cart Model, add items to cart and save to DB. Convert Cart model to cart data and save it to HTTP session. Any update/ edit update underlying cart in DB and update data snap shot in Session. When user click on view cart page, just pick cart data from Session and display to customer. I have following queries regarding HTTP Session How good is it to store large data (Shopping Cart) in Session? How scalable this approach can be ? (With respect to Session) Won't my application going to eat and demand a lot of memory? Is my approach is fine or do i need to consider other points while designing this? Though, we can control what all cart data should be stored in the Session, but still we need to have certain information in cart data being stored in session?

    Read the article

< Previous Page | 484 485 486 487 488 489 490 491 492 493 494 495  | Next Page >