Search Results

Search found 34771 results on 1391 pages for 'java man'.

Page 226/1391 | < Previous Page | 222 223 224 225 226 227 228 229 230 231 232 233  | Next Page >

• java System.nanoTime is really slow. Is it possible to implement a high performance java profiler?

  - by willpowerforever

  I did a test and found the overhead of a function call to System.nanoTime() is at least 500 ns on my machine. Seemed that it is very hard to have a high performance java profiler. For enterprise software, suppose a function takes about 350 seconds and has 12,500,000,000 times of method calls. Therefore, the number of calls to System.nanoTime() is: 12,500,000,000 * 2 = 25,000,000,000 (one for start timestamp, one for end timestamp) And the overhead of System.nanoTime in total is: 500 ns * 25,000,000,000 = 500 * 25000 s = 12500000s. Note: all data from real case. Any better way to acquire the timestamp?

  Read the article

• Understanding the concept of inheritance in Java

  - by Nirmal

  Hello All.... I am just refreshing the oops features of the java. So, I have a little confusion regarding inheritance concept. For that I have a following sample code : class Super{ int index = 5; public void printVal(){ System.out.println("Super"); } } class Sub extends Super{ int index = 2; public void printVal(){ System.out.println("Sub"); } } public class Runner { public static void main(String args[]){ Super sup = new Sub(); System.out.println(sup.index+","); sup.printVal(); } } Now above code is giving me output as : 5,Sub. Here, we are overriding printVal() method, so that is understandable that it is accessing child class method only. But I could not understand why it's accessing the value of x from Super class... Thanks in advance....

  Read the article

• Need better Java application deployment strategy

  - by Jeff Post

  I have various Java Swing applications that are used by multiple users. My deployment strategy is to locate the .jar file on a network share, and users create shortcuts to that file. When the user launches an application, the file is copied to their machine and executed locally. This method allows for a single copy of the code and easy updating. The problem is that I can't update the file on the network share if any user is using the application at that time. I can't use Web Start because I don't have access to a cert for signing the jar. My current workaround is a separate application that copies the desired app to the user's local machine, launches the application, and then the launcher exits. There is a several second delay from when the launcher app exits and the user's app becomes visible. Can anyone suggest a better deployment method where I can easily update a central copy of the application, one where Windows XP won't maintain a lock on the file?

  Read the article

• Count How many lines in a Java String

  - by Simon Guo

  Need some compact code for counting how many lines in a string. It should be Java Code. And the string is separated by \r or \n will be considered as a separate line. For example, "Hello\nWorld\nThis\nIs\t" should return 4. The prototype is private static int countLines(String str) {...} Can someone provide a compact code? I have solution at here but it is too long, I think. Thank you.

  Read the article

• Replicating Java's DecimalFormat in C#

  - by Frank Krueger

  I am trying to replicate a subset of Java's DecimalFormat class. Below is what I've come up with. Does this look right to everyone? public class DecimalFormat : NumberFormat { int _maximumFractionDigits; int _minimumFractionDigits; string _format; void RebuildFormat () { _format = "{0:0."; _format += new string ('0', _minimumFractionDigits); if (_maximumFractionDigits > _minimumFractionDigits) { _format += new string ('#', _maximumFractionDigits - _minimumFractionDigits); } _format += "}"; } public override string format (object value) { return string.Format (_format, value); } public override void setMaximumFractionDigits (int n) { _maximumFractionDigits = n; RebuildFormat (); } public override void setMinimumFractionDigits (int n) { _minimumFractionDigits = n; RebuildFormat (); } public override void setGroupingUsed (bool g) { } public static NumberFormat getInstance () { return new DecimalFormat (); } }

  Read the article

• Implementig Java Iterable<E> interface

  - by Metz

  Hi, i wrote this code: public class C1 implements Iterable<NC1> { private LinkedList<NC1> list; public static class NC1 { ... } ... x public Iterator<NC1> iterator() { return list.iterator(); } } but eclipse whines (at the x-ed line): - The return type is incompatible with Iterable<NC1>.iterator() - implements java.lang.Iterable<NC1>.iterator i don't understand where the mistake is. thanks in advance.

  Read the article

• Java Socket Disconnect Reporting vs. C# Disconnection

  - by ikurtz

  in C# when a sockets connection is terminated the other node is informed of this before terminating the link thus the remaning node can update the connection status. in Java when i terminate a communication link the other node keeps reporting the connection as valid. do i need to implement a read cycle (makes sense) that reports the connection as lost when it recieves a -1 during read (in C# this is 0 i think)? thank you for your insight. EDIT: thanks to you both. as i suspected and mentioned in my post that an additional check is required to confirm the connected state of a connection.

  Read the article

• php java in memory database

  - by msaif

  i need to load data as array to memory in PHP.but in PHP if i write $array= array("1","2"); in test.php then this $array variable is initialized every time user requests.if we request test.php 100 times by clicking 100 times browser refresh button then this $array variable will be executed 100 times. but i need to execute the $array variable only one time for first time request and subsequent request of test.php must not execute the $array variable.but only use that memory location.how can i do that in PHP. but in JAVA SEVRVLET it is easy to execute,just write the $array variable in one time execution of init() method of servlet lifecycle method and subsequent request of that servlet dont execute init() method but service() method but service() method always uses that $array memeory location. all i want to initilize $array variable once but use that memory loc from subsequent request in PHP.is there any possiblity in PHP?

  Read the article

• Java: is Exception class thread-safe?

  - by Vilius Normantas

  As I understand, Java's Exception class is certainly not immutable (methods like initCause and setStackTrace give some clues about that). So is it at least thread-safe? Suppose one of my classes has a field like this: private final Exception myException; Can I safely expose this field to multiple threads? I'm not willing to discuss concrete cases where and why this situation could occur. My question is more about the principle: can I tell that a class which exposes field of Exception type is thread-safe? Another example: class CustomException extends Exception { ... } Is this class thread-safe?

  Read the article

• Lightweight messaging (async invocations) in Java

  - by Sergey Mikhanov

  I am looking for lightweight messaging framework in Java. My task is to process events in a SEDA’s manner: I know that some stages of the processing could be completed quickly, and others not, and would like to decouple these stages of processing. Let’s say I have components A and B and processing engine (be this container or whatever else) invokes component A, which in turn invokes component B. I do not care if execution time of component B will be 2s, but I do care if execution time of component A is below 50ms, for example. Therefore, it seems most reasonable for component A to submit a message to B, which B will process at the desired time. I am aware of different JMS implementations and Apache ActiveMQ: they are too heavyweight for this. I searched for some lightweight messaging (with really basic features like messages serialization and simplest routing) to no avail. Do you have anything to recommend in this issue?

  Read the article

• Java Caching on distributed environment

  - by Naren

  Hi, I am supposed to create a simple replicated cache using java for internal purpose which will be used in a distributed environment. I have seen oracle has implemented Replicated Cache Service. http://wiki.tangosol.com/display/COH32UG/Replicated+Cache+Service The problem I am facing is while doing an update or remove, I acquire lock on other cache's to the point the cache get's updated and notifies others of the change. This is eventually going into a dead lock situation, while removing. Is there any strategy I should follow while updating or removing from cache's. Can I implement a replicated cache without having a primary cache?? Thanks, Naren

  Read the article

• Java library for converting Word documents to PDFs or images

  - by mieze

  Hey there What I need to do is convert Microsoft Word .doc files to PDFs or images. This has to occur in Java. I have done a fair bit of investigation already. I've tried Davisor Publishor but it doesn't give me the accuracy that I need - for instance text overlapping in the output document. Adobe has something called LiveCycle. Anyone tried this? It looks quite massive and a bit of overkill (its an "integrated server solution"). Sounds expensive. Saying that, it doesn't have to be free, or cheap. Even if you just know some names, please shout them my way. Many thanks in advance. Doug

  Read the article

• Java Scheduling Calendar

  - by cedric

  Hi. I have a j2ee web application which supports scheduling of execution of jobs. I am looking for a free calendar component written in java which allows scheduling functionalities as well as capable of changing view mode of tasks either by viewing taks for whole year, month view, week view, day view. Do you have any suggestion. Im sorry something came up with the implementation. I dnt have to use this calendar for triggering or calling jobs. I just need to retrieve schedules from database and display it in diff view modes. SO it's just some kind of GUI functionality

  Read the article

• Java: JPA classes, refactoring from Date to DateTime

  - by bguiz

  With a table created using this SQL Create Table X ( ID varchar(4) Not Null, XDATE date ); and an entity class defined like so @Entity @Table(name = "X") public class X implements Serializable { @Id @Basic(optional = false) @Column(name = "ID", nullable = false, length = 4) private String id; @Column(name = "XDATE") @Temporal(TemporalType.DATE) private Date xDate; //java.util.Date ... } With the above, I can use JPA to achieve object relational mapping. However, the xDate attribute can only store dates, e.g. dd/MM/yyyy. How do I refactor the above to store a full date object using just one field, i.e. dd/MM/yyyy HH24:mm?

  Read the article

• Appending Integer array elements in Java

  - by Neville

  I have an array, say int a[]={2,0,1,0,1,1,0,2,1,1,1,0,1,0,1}; I need to append each of the 5 neighboring elements and assign them to a new array b with length=(a.length/5); and i want to append the 5 neighboring elements so that I have: int b[]={20101,10211,10101}; I need to do this for various length arrays, in most cases with length of a being greater than 15. Any help would be greatly appreciated, I'm programming in Java. Thanks in advance.

  Read the article

• Write large PDFs with Java sequentially

  - by Benjamin Muschko

  I am looking for a Java library that let's you write large PDFs sequentially with a minimum amount of memory. Most of the libraries I had a look at has to build up the document in memory first before you can actually write it. The problem I have to deal with are OutOfMemoryErrors. It would be great if I could flush the writer programmatically whenever needed e.g. for each page. Does anyone have any recommendations? I need something with a license along the lines of the LGPL (so not the GPL or the Affero GPL that iText uses).

  Read the article

• In java getting different value for TimeZone.getDefault().getID() on different system

  - by Deepak Chaudhry

  I am getting different value for TimeZone.getDefault().getID() on different systems. For example, in case of Indian standard time, On one of the system we are getting "GMT+5:30": while on another we are getting "Asia/Calcutta". We are expected to get "Asia/calcutta" strings on all machines. Why is there an inconsistency for such behavior? Is there any way to get consistent behavior across different systems windows/MAC? What is the best way to get client time zone programmatically using Java?

  Read the article

• Java Non-Blocking HTTP Server

  - by Marcus

  I have written an application using embedded Jetty that makes network calls to other services. I presume that the serving threads are idle whilst waiting for the network calls to complete. Is there any way to have a worker thread that switches between requests to perform work that can be done at the current time and then when the network calls return also handle that? A request would be returned when all work has been completed for it. I know this is a common paradigm, and I have used it for non-blocking TCP networking, but I'm unsure as to how to achieve this on a Java HTTP server whilst also waiting on external results. Any links or explanations are appreciated. Thanks

  Read the article

• Accessing every child class of parent class in Java

  - by darkie15

  Hi All, I have to implement a logic whereby given a child class, I need to access its parent class and all other child class of that parent class, if any. I did not find any API in Java Reflection which allows us to access all child classes of a parent class. Is there any way to do it? Ex. class B extends class A class C extends class A Now using class B, I can find the superclass by calling getSuperClass(). But is there any way to find all the child classes once I have the parent class i.e. class B and class C?? Regards, darkie

  Read the article

• Monitor file in Java on Linux 64bits

  - by Tim

  I'd like to be notified when a file has been created, deleted or changed, but not using polling mechanism. I have surveyed related Java API that can use.(EX:JNotify, JPathWatch and JXFileWatcher) Those APIs provide file monitor by using native component on OS. But I met the same problem is that they can't run on Linux 64bits, because native component in those APIs donen't support Linux 64bits, and this confused me for a long time. I also know that there'll be a WatchService API as part of NIO2 in JDK7, but JDK7 has not released yet. So, can any one suggest me a better solution? Very Thanks.

  Read the article

• creative way for implementing Data object with its corresponding business logic class in java

  - by ekeren

  I have a class that need to be serialized (for both persistentcy and client-server communication) for simplicity's sake let's call the classes Business a BusinessData and I prefix for their Interfaces. All the getter and setter are delegated from Business class to BusinessData class. I thought about implementing IBusinessData interface that will contain all the getter and setters and IBusiness interface that will extend it. I can either make Business extend BuisnessData so I will not need to implement all getter and setter delegates, or make some abstract class ForwardingBusinessData that will only delegate getter and setters. Any of the above option I lose my hierarchy freedom, do any of you have any creative solutions for this problem... I also reviewed DAO pattern: http://java.sun.com/blueprints/patterns/DAO.html

  Read the article

• DataGrid In Java Struts Web Application

  - by Anand

  Hi After scouring the web I have edited my question from the one below to what it is now. Ok I seem to understand that I don't need all the capabilities of excel right now. I think i am satisfied having a data grid to display data. Basically i am working on Struts 2 and I wat my jsp page to have an excel like feel and hence looks like even a datagrid is sufficient. I came across This Technology I am not sure whether I must go ahead and use it. Any other suggestions, alternatives are welcome The older version of the question "I have a java web application running on windows currently. I may host it in future in a Linux Server. My application allows people to upload data. I want to display the data they have uploaded in an excel file and render it in a portion of my webpage. How do I go about this ?"

  Read the article

• Using type hints in Clojure for Java return values

  - by mikera

  I'm working on some Java / Clojure interoperability and came across a reflection warning for the following code: (defn load-image [resource-name] (javax.imageio.ImageIO/read (.getResource (class javax.imageio.ImageIO) resource-name))) => Reflection warning, clojure/repl.clj:37 - reference to field read can't be resolved. I'm surprised at this because getResource always returns a URL and I would therefore expect the compiler to use the appropriate static method in javax.imageio.ImageIO/read. The code works fine BTW so it is clearly finding the right method at run time. So two questions: Why is this returning a reflection warning? What type hint do I need to fix this?

  Read the article

• A simple way (in java) to remove headers

  - by Andersson Melo

  I need remove non-xml tags from file generated by another program. The file is some like this: Executing Command - Blah.exe ... -----Command Output----- HTTP/1.1 200 OK Connection: close Content-Type: text/xml <?xml version="1.0"?> <testResults> <right>7</right> <wrong>4</wrong> <ignores>0</ignores> <exceptions>0</exceptions> </finalCounts> </testResults> Exit-Code: 15 How to remove the non-xml text easily in java?

  Read the article

• Efficient persistent storage for simple id to table of values map for java

  - by wds

  I need to store some data that follows the simple pattern of mapping an "id" to a full table (with multiple rows) of several columns (i.e. some integer values [u, v, w]). The size of one of these tables would be a couple of KB. Basically what I need is to store a persistent cache of some intermediary results. This could quite easily be implemented as simple sql, but there's a couple of problems, namely I need to compress the size of this structure on disk as much as possible. (because of amount of values I'm storing) Also, it's not transactional, I just need to write once and simply read the contents of the entire table, so a relational DB isn't actually a very good fit. I was wondering if anyone had any good suggestions? For some reason I can't seem to come up with something decent atm. Especially something with an API in java would be nice.

  Read the article

< Previous Page | 222 223 224 225 226 227 228 229 230 231 232 233  | Next Page >