InputStream available() question

Crosspost
Is it unusual for an input stream to say that there are X bytes available but when calling
int foo = in.read(myArray, intstart, myArray.length);to read less than the available?
foo = X - something?
Thanks

Thank you for the response. This is exactly what I'm
seeing though. I find it puzzling.
byte[] buffer = new byte[512];
int MAX = in.available(); // This is returning 972
bytes
if(MAX > buffer.length) MAX = buffer.length;
intTotal = in.read(buffer, 0, MAX); // intTotal =
155 ???Should I be looking elsewhere for the issue. The
stream is from a data socket.can u try this
int MIN = in.available();
buffer = new byte[MIN];
intTotal = in.read(buffer, 0, MIN);

Similar Messages

Unable to understand InputStream.available() method, need some help

dear friends,
The following is my doubt. please kindly help me in this. this will help me a lot in understanding some consepts.
Environment: i am using jdk1.4.1_01 on windowsxp.
i am using IE6.0 to make requets.
My requirement:
what i am actually trying to do is i want to see the raw material
send by the browser when we made a request to the server
by the browser.basically i want to see the request line
and headers as it is that is send by the browser to the server.
so i thought to code a server that can print the request send
by the browser as it is on the command window.
i had taken two examples and i am running Server2.java (look at the bottom for this code)and i made a 25 requests to the server2 program
which is running on port 8080 by the browser. here only once or twice in 25
times i was able to see the requests send by the browser.i tried hard and
found that InputStream.available() method is returning 0 even though the
request is sucessfully send to the port 8080 that is to the server2 program
which is listening to port 8080.
so in this process of experimenting i took Server3.java(i am sending this file
also as an attachment) which is using multithreading. in this also i did modification
as i did in Server2.java. the thing is here i am able to succed. here
InputStream.available method is returning the correct number of bytes
that are arrived on the port and are available to the InputStream.here
when ever i made a request from the browser to Server3.java i am able to
see the raw data send by the browser without failure.
i could not understand why InputStream.available() is returning 0
often(not all the time) and why it is giving the desired result when i
used it in Server3.java ?
i looked into the documentation and it says " InputStream.available() Returns the number of bytes that can be read (or skipped over) from this input stream without blocking
by the next caller of a method for this input stream."
so the thing i could not understand is what is blocking the InputStream
in the first case.if i could undrstand the internals of how this
method is working it will help me a lot.if i could understand this i
will know what is the right situations to use this method.
Thanking You.
/*Shows how to develop a simple network server
Author : Team -J
Version : 1.0 */
import java.net.*;
import java.io.*;
class Server2{
static public void main(String[] args)throws Exception{
     // create a new Server Socket
     try{
          ServerSocket ss = new ServerSocket(8080,1);
     while(true){// set queue length to 1
          // wait for the connections
          Socket s = ss.accept();
          // get the output stream associated with socket
          // to write something to the socket
          PrintStream ps =new PrintStream( s.getOutputStream());
          InputStream is = s.getInputStream();
          ps.println("I am ready to provide xxx Service");
int len=is.available();
          if(len !=0)
          byte b [] = new byte[len];
          int k =is.read(b,0,(len-1));
          for(int i =0;i<k;i++)
               char c = (char)b;
               System.out.print(c);
          // close the connection
          is.close();
          s.close();
     }catch(Exception e){}
/*Shows how to develop a simple network server
Author : Team -J
Version : 1.0 */
import java.net.*;
import java.io.*;
class Server3{
static public void main(String[] args)throws Exception{
     // create a new Server Socket
     try{
          ServerSocket ss = new ServerSocket(8080,1);
          while(true){
               // wait for the connections
               Socket s = ss.accept();
               ServerThread st = new ServerThread(s);
               st.start();
     }catch(Exception e){}
class ServerThread extends Thread{
Socket s;
     public ServerThread(Socket s){
     this.s = s;
     public void run(){
          try{
          PrintStream ps =new PrintStream( s.getOutputStream());
          InputStream is = s.getInputStream();
          int len=is.available();
          ps.println("I am ready to provide xxx Service");
          if(len!=0)
          byte b [] = new byte[len];
          int k =is.read(b,0,(len-1));
          for(int i =0;i<k;i++)
               char c = (char)b[i];
               System.out.print(c);
          is.close();
          s.close();
          }catch(Exception e){}

so the thing i could not understand is what is
t is blocking the InputStream
in the first case.Blocking means the thread goes to sleep waiting for more data to arrive. InputStream.available() shows how many bytes have already arrived, not how many remain to be sent.

How to override InputStream.available()

Hi,
InputStream.available() always returns zero.
now i have a requirement where I want to know total size of data in an InputStream.
Note: I don't want to read all the data byte by byte into an byte[] etc etc.
the reason is that data can be huge and i don't want to keep it in memory.
Regards
Apratim

I'm glad you don't want to keep huge amounts of data in memory but I would consider 512Mb as huge myself.
To override InputStream.available() all you have to do is override InputStream.available(). But if the information you want isn't available, tough.
FileInputStream.available() returns the length of the unread portion of the file, although I don't rely on it personally. Various other implementations of available() return zero. For example, SSLSocket.getInputStream().available(), because the stream can't know without decrypting, and it mightn't have an entire cipher block to decrypt, and you wouldn't want it to block getting the rest of the cipher block so it could decrypt so it could tell you how much data was available without blocking, so what else can it do?

Newbie Oracle Enterprise Manager 11g feature availability question

Newbie question here. I am new to Oracle 11g and new to this forum. I ran a search on this question and came up empty so hopefully there is a kind and knowlegable soul wo can help.
I recall in earlier versions of Oracle Enterprise Manager for earlier versions of Oracle there was something called Oracle Enteprise Manager Reporting accessible from the OEM web.
One of its key features was the ability to make custom "Additional Reports". In our current environment this is installed and works great. I don't know if it was an add on to OEM, or if it was built in. It was built a long time ago and I wasn't arround for that build. All I know is it works and it suits our needs.
Well we are now trying to build a new Oracle dev box to replace the current dev environment. We would prefer to not lose any existing functionality we have... and if possible not have to reinvent the wheel. The new box has Oracle 11g.
**Here comes the dumb newbie questions. **
Does Oracle 11g Enterprise Manager support 9i-style Enterprise Manager Reporting and Custom Reports?
Is it called that in 11g or has it been renamed to something else?
Is it it a simple matter of configuration or is it an add on that needs to be installed?
Any help would be most appreciated.
Thanks,
Wayward Oracle Newbie looking for an Oracle Home

Oracle 11g does not support 9i-style custom reports. There is a new reporting framework - Information Publisher available in Grid Control 10+ versions. The new reporting framework does support custom reports as well. Click on the Reports tab to access the functionality.
Regards,
Leslie

InputStream.available()

Hi,
InputStream is = socket.getInputStream();
int n = is.available();
n don't return number of bytes available in the InputStream, it is always 0.
Why?
~Hill

available is not a good function to use because it's behavior is badly defined.
It is not implemented correctly in many input streams. This is because of the nature of the streams, they generally are not buffered very well in the lower systems. The InputStream api says that the available function SHOULD be overridden but is doesn't have to be.
Especially now with the new NIO classes, you don't need to use this functionality at all. This is one of the reasons that the NIO was created, as if this functionality actually worked correctly, one of the main reason for NIO ( the problem of one reader per thread ) would be eliminated.

InputStream.available() doen't work always

I have a remote HTTP resource of 11kb that I want to retrieve through InputStream obtained from HttpURLConnection (of J2SE) and HttpConnection (of J2ME).
If I download it byte after byte with this code ("is" is InputStream instance from Http) :
int ch;
ByteArrayOutputStream f = new ByteArrayOutputStream();
while ((ch = is.read()) != -1)
f.write((byte)ch);
it works fine on J2ME on my mobile phone (Nokia 6680), with WirelesseToolkit Emulator and also in my J2SE application.
But if I try to fetch the resource with read(array) it works only on my Nokia 6680 and not in WIrelessToolkit Emulator and J2SE application.
The code I used is this:
int byteDisp = is.available();
byte[] arraySwap = new byte[byteDisp];
is.read(arraySwap);
The problem is that is.available doesn't give me the actual value of bytes of my remote resource when I use the code on my desktop pc (with J2ME emulator or J2SE application). So I think that the problem is caused by Internet connection because it works fine on my mobile phone.
Can you help me?
I don't want to use the while with the byte read.
Thanks you,
ReX

>
Now it works fine everytime and everywhere, do you
think that this solution could give me some
problems?The loop means that the CPU is doing work it doesn't need to.
You can solve this by doing something like the following pseudo code demonstrates.
    byte buffer = new byte[1]; // Note the '1'
   socket.ReadBlock(buffer) // Read only one byte and block till we get it
   AccumlateMessage(buffer)
   while(socket.available)
       buffer = new byte[socket.AvailableSize];
       socket.ReadBlock(buffer)
       AccumlateMessage(buffer)
For the above you can choose a value besides '1' if it seems reasonable for the actual protocol that you are using and with the possible error cases taken into account.

Timesten high availability question

I have a case presented here and wanted to know if it is actually possible to implement.
Let us consider four nodes with timesten (11.2) installed in all of them. A datastore with the same name is created on each of the four servers. Two of these servers are in location A and the other two in location B. Servers in location A have replication defined between them and similarly servers in B have replication defined between them. But note that there is no replication defined between any server in location A with any server in location B.
The basic idea of this entire setup is to maintain high availability of timesten at any point of time (in case of natural disasters, etc..) irrespective of the location of the servers
Now, we have oracle software installed in four other systems. Two of these servers are in location A and the other two are in location B. Note that they are not installed on the same box as Timesten.
Scenario 1:
Question: Timesten in location A goes down, how is the high availability taken care of?
Answer: Timesten in the other server in location A should come up and because of the replication process, this will solve the problem.
Is this correct? I think it is.
Scenario 2:
Question: Timesten installed on both the nodes at location A go down, how is high availability taken care of?
Answer: ?
Please remember from above that timesten does not have a replication policy defined between any server in location A with any server in location B. The requirement says that we should be able to recover all the latest data that the nodes at location A had, by pulling it from oracle DB at location A and putting it into TT server in location B. I would like to know if it is possible to do this?

Hello,
Your approach is correct in designing a Disaster Recovery architecture for TimesTen and Oracle Database. TimesTen supports an Active-Standby pair topology that works well with integrating with the Oracle database within a particular site. However, like for any geographical based replication, it is recommended to configure replication across the WAN using the Oracle Database GoldenGate or Streams technologies in ASYNC mode for better throughput and efficiency. It is also recommended to compress replication traffic across the WAN between the Oracle databases.
So while using the Oracle Database to replicate transactions across the WAN is the right thing to do (using Streams Replication or GoldenGate between the two Oracle databases (assuming using an Oracle RAC 2-node cluster in each site), you will not be able to guarantee that any transactions in site A has made it to site B. GoldenGate and Streams technologies have the ability to replicate the data bi-directionally. What this means is that when site A recovers, transactions that had been trapped there (either between TimesTen and the Oracle DB or in the Oracle DB transaction logs), will attempt to replicate again to site B, so it is important to set up a conflict detection/resolution approach which is possible to do in either GoldenGate or Streams.
Note that Oracle Data Guard replication is not supported with TimesTen in such a configuration across the WAN where TimesTen datastores need to be maintained in both sites.
To fully answer the question, however, we should get into the details of the type of cache group tables that you intend to use in TimesTen. If using TimesTen as just a read-only cache while all inserts/updates happen in the Oracle database, then OracleDB would be regarded as the database of record and it would be used to handles all changes while data changes get auto-refreshed from teh Oracle databases in each site into the respective TimesTen tables.
If the application will be looking to take advantage of fast writes into TimesTen using AWT (async writethrough cache group tables), then it is recommended to configure those tables to be DYNAMIC AWT tables so that if a failover to site B takes place and the data is not in TimesTen (but it is in the Oracle Database), it will be automatically loaded on demand as needed from the Oracle database in site B. Note however that there are restrictions that exist with DYNAMIC load on demand cache groups that you need to look into to find out whether those would work in your application's case (particularly, load on demand works only if the where clause includes an equality predicate on the primary keys, foreigh keys, or unique indexes, etc...)
To fully answer your question on non data loss across geographies, you'd have to use Synchronous replication between TimesTen and Oracle using Synchronous Writethrough Cache Groups and SYNC replication in Streams for example between the two geographies. Neither of those configurations are used to my knowledge in the field because they are very non optimal and carry huge response time expense, which slows down replication considerably and affects application response times.
My assumption also is that the need for the Oracle database is because all data does not fit into memory. If the data does fit into memory, then you could also consider a pure timesten replication across the two sites using an active-standby pair on site A and a read-only subscriber on site B that would be made ACTIVE only in the case of a disaster on site A. Once site B takes over, you can also create an active-standby pair in site B based on the newly elected ACTIVE datastore in that site. In all these cases, it is recommended to use SYNC 2-SAFE replication between TimesTen datastores in the same site and ASYNC replication between the two sites.

InputStream available() variance in functionality

We have a Webservice program which sends a SOAP request with OutputStream and captures the SOAP response with InputStream. We are using available() method of InputStream to fetch the input response. This method used to work correctly for the below OS and Java version
[user2@HENDRIX ~]$ java -version
java version "1.5.0_05"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_05-b05)
Java HotSpot(TM) 32-Bit Server VM (build 1.5.0_05-b05, mixed mode
We have upgraded the system to below version and the webservice program is stripping off the SOAP request to some extend and unable to fetch the full SOAP XML response
[user1@HERMES ~]$ java -version
java version "1.6.0_11"
Java(TM) SE Runtime Environment (build 1.6.0_11-b03)
Java HotSpot(TM) 64-Bit Server VM (build 11.0-b16, mixed mode)
But the same program without change in the code worked for earlier versions. Please let us know do we have any change in the available() method behaviour.

Sounds like you are expecting available() to return the length of the stream. It cannot be reliably used for this process and should never have been used in the first place. [available()|http://java.sun.com/j2se/1.4.2/docs/api/java/io/InputStream.html#available%28%29] return the number of bytes that can be read without blocking and says nothing about how may bytes the stream contains.

InputStream object question

Hello friends,
I understand that you can't create an object using an abstract class, such as InputStream. But how come the constructor of the InputStreamReader can accept a InputStream as object?
Thx

Thank you all for the comments and explanations. I am sorry my question wasn't clear enough in the beginning. I wasn't trying to get any input from any particular stream problem. I was just little confused on the concept of abstract class that's all.
When I do
<pre>
InputStream inReader = new InputStream();
</pre>
I will get error like this:
<pre>
InputStreamTest.java:7: java.io.InputStream is abstract; cannot be instantiated
InputStream inReader = new InputStream();
^
</pre>
But when I do:
<pre>
InputStream inReader =System.in;
</pre>
I got no error. I thouht both are creating an object "inReader", why first gave error and second doesn't?
Thanks in advance for helping. ;-)

Solaris 10 Update 5 availability question

Did I miss the release of Update 5? I see it mentioned in docs.sun.com, but not in downloads.
Or does anyone have availability date for it? It seems overdue timewise.

Thanks Darren,
You are most helpful as always.
P.S.Are you still at Taos? I was in NY's office ca 99'-01'
Slava

Cisco Prime Infrastructure 2.1 High availability Question

Hello All,
I am configuring high availability for two prime infrastructure 2.1 servers. I have configured manual HA between the servers. I need to know what will be the configuration in the devices ( switches,routers etc.) for proper working of the HA. For example
Should we need to configure both the prime infra servers as snmp hosts in the devices??. If we have to when an event happens the switch well unnecessarily send the traps to the secondary even when the primary is alive??.
If anyone has a copy of the configuration of such a set up please share it with me.
Thanks and Regards
Shabeeb

Hi Shabeeb,
You are correct on that part that unnecessarily devices will try to send traps to the secondary server if you specify that in the device's config. I don't think it should be a concern , this is expected.
otherwise you need to configure them later once the PI server fail over to secondary .
If you have any other doubt ,kindly ask.
Thanks-
Afroz
***Ratings Encourages Contributors ***

Adobe Support Availability Questions and Feedback

I am currently having an issue with Adobe Shape not saving/syncing to my CC Library, on a Saturday evening here in the U.S.A. I decided to contact Adobe Support. After navigating to this page:
I clicked on chat as was recommended. I tried to be more specific about Adobe Shape, but when I clicked on choose a different product, it just looped me back to the start. (At the start, though many other mobile apps were available to select, neither Adobe Shape, nor Shape, was available.)
After waiting for almost an hour in queue, I was informed that I was chatting with the installation dept, and should try chatting again during business hours, as chatting about troubleshooting a specific issue or product is not available during non-business hours.
If this is indeed the case, then why was Chat recommended to me after I selected troubleshooting? Why is there no mention of this on any of your support pages? Displaying this fact somewhere in your Support pages might greatly shorten your weekend and night queues greatly.
I'm also wondering, is this is a policy change? I do seem to vaguely recall getting support through chat for specific issues during off hours in the past.

neat. here is the Adobe SendNow app I've never heard about.
I'd sure as hell rather be using this than yousendit! I've been paying them 50 bucks a month and don't enjoy the service at all.
this would be another good thing to have tied into our cloud homepages. you could see your file upload, confirm they got it. blah blah.
https://www.acrobat.com/sendnow/en/home.html
I think I'm closer to finding the basecamp thing.... maybe its called echosign... no.. workspaces? yes.
Adobe workspaces is the BaseCamp of Adobe that I was looking for.
https://workspaces.acrobat.com

FTTC Help - Cabinet / Availability Question

Hi Guys,
I'm not sure if anyone will be able to assist with this as everyone I have spoken to at BT seem to be stumped, however, I am due to speak to someone "technical" tomorrow to see if they have any ideas. Saying this, my current responses don't seem to be getting me anywhere as no one seems to have a clue!
So I thought I would turn to here as I can see several technical questions, but not seem to be the same as below.
I ordered Infinity based on the postcode to where I was moving on the 7th January, as of the 24th January they enabled the phoneline, this was fine, then suddenly didn't seem to work or be possible for any sort of broadband capability. This went on for about a week and then again it was "fine", I was then rang last week (4 weeks after placing my order) and told that BT cannot provide Infinity due to the line not being enabled to do so. This was due to their computer telling them I can't have it, no other reason, as you can imagine, this isn't really what I signed up for and was somewhat annoyed by this "customer service". I have done my own research which i've placed below and no one can say to why the below won't allow me to have the fibre service. Saying that, I've not spoken to anyone techincal yet as I only seem to be able to speak to sales teams / "the offline team".
My postcode is LS28 6PN. The area is enabled for FTTC, including the cabinet that I am connected to (Cabinet 7 - Pudsey). The cabinet is outside the address where I live, I can see it whilst I type this email.
The phone number that I have been given also connects to Cabinet 7, Pudsey, however, does not allow me to obtain FTTC.
Upon moving in, I did many checks including that one properties around the area within 50 meters of where I live, all of which can get Fibre by checking on the BT Wholesale site. (Some are small shops and have phone numbers which state they too connect to Cabinet 7, but are able to get FTTC.
Below is the checks I can do using the post code and exact house number:
Below is using the phone number I have been given last week by BT:
Below is using a phone number of the property opposite my house, the cabinet (7) is on my side of the road, closer to me than it is to them:
I've done this on a few properties around where I live and they are all showing the same information, just where we are they won't allow it via the phone number I have been allocated.
Upon speaking to my friend, who was an Openreach engineer he suggested I ask that the routing information is checked. Does anyone have any ideas on this?
As mentioned all of the information given states I should be able to receive the fibre service, the below states 100% and I am about 900 metres from the exchange upon checks. The only thing that doesn't seem to work is the phone number I have given by BT upon signing up for the service over 5 weeks ago.
Thanks in advance for any assistance you guys can provide, I'm not sure if anyone will have any ideas but if you do please let me know as I don't seem to be getting anywhere with BT.
Apologies for anything I may have missed as this is my first post... Please let me know if you think you can help and if you need any further information from me.
Cheers,
Ben

Hi benjolly,
Welcome and thanks for posting!
It does look like this involves an update from our end. I'm happy to give you a hand to get this sorted. Click on my username and under the section "about me" you'll see the link to get in touch with us.
Please include the link to this thread when you complete the form and whenever we've received your details we'll take it from there.
Thanks a million,
Robbie
BTCare Community Mod
If we have asked you to email us with your details, please make sure you are logged in to the forum, otherwise you will not be able to see our ‘Contact Us’ link within our profiles.
We are sorry that we are unable to deal with service/account queries via the private message(PM) function so please don't PM your account info, we need to deal with this via our email account :-)
If someone answers your question correctly please let other members know by clicking on ’Mark as Accepted Solution’.

Kodo Availability Questions

Hi,
I hsave been able to get only limited information fronm Pre-sales on the following so I thought I would ask here. Or can you refer me to another contact for a potential new customer? Email to [email protected] bounces.
I have the information that the Enterprise,
Professional, and Basic editions of Kodo cost respectively:
Purchase: $5000/ $1850/ $1100 per developer
Support: 21%/$750/$650 per year per developer
(1) Does the JPA compoment run on WebSphere 6.1 on Windows (which is Java 5)? I cannot find instructions foe installing it on WAS in the doxumentation. Installing JDO is described but not installing JPA.
(2) I assume that there is no runtime charge per CPU, just a
per-developer charge??
(2) The following press release
http://www.bea.com/framework.jsp?CNT=pr01721.htm&FP=/content/news_events/press_releases/2006
says:
"Additionally, when Apache releases the 1.0 version of OpenJPA, BEA will
extend its 24x7 local language production support to cover it, providing
a â€œone-stop support shopâ€ for IT operations managing heterogeneous
open-source and Java EE environments."
and another earlier new article says that the cost of OpenJPA support
alone would be about $1050 per developer per year.
Is there an estimated availability date for
OpenJPA support alone, and am I correct that there is no purchase cost in that case,
just the support charge?
Thanks!
Don Brady
[email protected]

Can anyone shed some light on how we get statement caching working whilst using JNDI to specify the db connection details? Is this possible???
Any info/help would be very much appreciated as statement caching is something we would now like to enable.
Many thanks,
Nick

Yet another "font not available" question

Hello,
First, I'm using FM 8.1.3 on Windows (XP). So I don't have the Font Pod or any of that other FM 10 good stuff.
I'm trying to open a chapter in a book that contains both English and Simplified Chinese text. The error I keep getting says that "MS Mincho" is not available, and a Kazuka Gothic font is being substituted. I click OK and the file opens. I save and close the file. Then I try to open it again and the error is still there. All of the chapters in the book have the same problem.
I saved one of the chapters as a .mif and opened that as a text file. I searched for "Mincho", and it wasn't there. I searched for "FFamily" in the file and didn't find anything similar to Mincho in any of the references. There were many entries but no unfamiliar fonts being referenced.
I also tried the trick of opening all the files, accepting the substitution for each, and then trying to update the book. That doesn't seem to work. The update is finished much too quickly. Something flashes by really quickly in the status bar of the book file - I thought I saw titles of a couple of the chapters (different title each time I ran the update), but (1) the book file does not have a new time stamp, even if I do something that should trigger a change to the book file, eg, change the order of a couple of chapters in the book file, and (2) there's no error message. I don't think it actually did an update. (When I try to update the book with all the chapter files closed, I'm still getting the "could not open file because of missing font" errors.)
Are there any other things I might try?
Thanks,
Joyce

Joyce,
You have your preferences set to Remember missing fonts. When you open a file with missing fonts, FrameMaker warns you; but when you click OK, it opens the file with the substituted font just to display the document. FrameMaker does NOT substitute the font permanently, just for the current display. If you make a change and save the file, you are saving any content changes but not the font substitution.
If you are happy with the substituted font, you can open the preferences and uncheck Remember missing fonts. Then when you open the file, FrameMaker's response is as before; however, when you save the file, the font substitution is saved in the file.
You can then turn Remember missing fonts back on, if you want. The purpose of this feature is to allow you or others to edit the document without actually having the font on your system but retain the font information in the file.
Van

InputStream available() question

Similar Messages

Maybe you are looking for