How do I print a .dwg file from Java?
Is there is an API for accessing and passing the DWG AutoCAD file to the printer for printing?
Dwglib is a Java library for accesing DWG files. It is essentially a port from the Pythoncad DWG reading classes by Art Haas. jdwglib manages complex DWG objects allowing users to employ these objects directly in their applications.
You'll to find an API that allows you to read an AutoCAD dwg file. I haven't seen any Java ones, but you might be able to start from the .NET one following:
http://code.google.com/p/tf-net/wiki/DwgReaderWriter
Once you've found an API, then it might be as simple as printing whatever you render.
Related
I have some pig output files and want to read them on another machine(without hadoop installation). I just want to read a tab-seperated plain text line and parse it into a java object. I am guessing we should be able to use pig.jar as dependency and be able to read it. I could not find relevant documentation. I think this class could be used? How can we provide the schema also.
I suggest you to store data in Avro serialization format. It is Pig-independent and it allows to handle complex data structures like you described (so you don't need to write your own parser). See this article for examples.
Your pig output files are just text files, right? Then you don't need any pig or hadoop jars.
Last time i worked with Pig was on amazon's EMR platform, and the output files were stashed in an s3 bucket. They were just text files and standard java can read the file in.
That class you referenced is for reading into pig from some text format.
Are you asking for a library to parse the pig data model into java objects? I.e. the text representation of tuples & bags, etc? If so then its probably easier to write it yourself. It's a VERY simple data model with only 3 -ish datatypes..
I has a excel file with 4 excel sheets in it. Now i want to read or write to required excel sheets using java without using any third party lib.
I know i can read and write data using FileInputStream and FileOutputStream respecitvely. But i can handle the work sheets??
No, you can'not, There is numerous way in Java for reading/writing files, but there is no built-in support for MS Office/Excel spreadsheets. http://poi.apache.org/ - is a key to victory.
If your goal is to interface with data from an excel sheet from your Java application, I'd suggest to use the solutions suggested by other posters, it will save you a lot of work.
If, however, you want to be able to read excel files from Java (or any other programming language for that matter) 'just because you can' then you could take a look at this file and read the instructions on this web-page. I would warn you that it would take considerably more time to implement your own API if you base it only on the file-specs that are publicly available. You might want to check out the work done by the people from the Apache POI project to get an idea of how to approach it. Or (even better) contribute to the project. Here you can find out how to go about doing that
I'm trying to read excel file and pass all the data to DB. I found a few code examples but all of them required external jars. How can I read excel files using only the standard library?
IF you don't want to use a library then you will have to download the Excel file format specs from MS and write an Excel parser yourself (which is extremely complicated and takes > 10 years for one developer). For the OpenXML format spec see here and here.
Thus I really recommend using a library for that...
Try Apache POI - a free Java library for dealing with MS Office documents..
You can save as the excel file *.cvs and sperated ";". Then, you can read file line by line and get the columns which is getting from each token.
Microsoft excel uses a binary way to save its data, so manually reading excel files might be a hassle. If you could convert the excel (xls) to a comma seperated values (csv) file, then you can just read the file and split your input on the comma's.
This is a difficult problem. First off, it is not as simple as "adding a third party library". There are no existing EXCEL reading libraries that do not cost money and the one that I know that does work is very expensive AND has bugs in it.
One strategy is to create an Excel add in that reads the data and transfers it to your application by OLE or the clipboard or by a TCP/IP port or saves it to a temporary file. If you look in the source code for OPeNDAP.org's ODC project you can find an Excel add in and TCP capability to do this.
You can try referring to the reader in OpenOffice which is open source code, however, in my opinion that code is not easily refactorable into a private project for various reasons.
Microsoft has components and tools to open Excel files and expose them via COM objects.
You can also learn the BIFF format and write your own parser. You probably would want to write a parser for BIFF5, but be forewarned, this is a BIG project, even if you only parse a limited number of data types.
The interop library is slow and needs MS Office installed.
Many times you don't want to install MS Office on servers.
I'd like to use Apache POI, but I'm on .NET.
I need only to extract the text portion of the files, not creating nor "storing information" in Office files.
I need to tell you that I've got a very large document library, and I can't convert it to newer XML files.
I don't want to write a parser for the binaries files.
A library like Apache POI does this for us. Unfortunately, it is only for the Java platform. Maybe I should consider writing this application in Java.
I am still not finding an open source alternative to POI in .NET, I think I'll write my own application in Java.
For all MS Office versions:
You could use the third-party components like TX Text Controls for Word and TMS Flexcel Studio for Excel
For the new Office (2007):
You could do some basic stuff using .net functionality from system.io.packaging. See how at http://msdn.microsoft.com/en-us/library/bb332058.aspx
For the old Office (before 2007):
The old Office formats are now documented: http://www.microsoft.com/interop/docs/officebinaryformats.mspx. If you want to do something really easy you might consider trying it. But be aware that these formats are VERY complex.
Check out the Aspose components. They are designed to mimic the Interop functionality without requiring a full Office install on a server.
As the new docx formats are inherently XML based files, you can create and manipulate them programmatically with standard XML DOM techniques, once you know the structure.
The files are basically zip archives with an alternate file extension. Use the System.IO.Packaging namespace to get access to the internal elements of the file, then open them into a XmlDocument to perform the manipulation.
There are examples available for doing this, and the Office Open XML project on SourceForge may be worth looking at for inspiration.
As for the older binary formats, these were proprietary to MS, and the only way you're likely to get at the content from within is through the Office object model (requires an Office install), or a third party file converter/parser.
Unfortunately there's nothing first party and native to the .NET platform to work with these files.
What do you need to do with those file? If you just want to stream them to the user, then the basic file streams are fine. If you want to create new files (perhaps based on a template) to send to the user that the user can open in Office, there are a variety or work-arounds.
If you're actually keeping data in Office documents for use by your web site, you're doing it wrong. Office documents, even Excel spreadsheets and access databases, are not really an appropriate choice for use with an interactive web site.
If the document is in word 2007 format, you can use the system.io.packaging library to interact with it programatically.
RWendi
In Java world, there is also JExcelApi. It is very clearly written, from what I was able to see, much cleaner then POI. So maybe even a port of that code to .NET is not out of the question, depending of course you have enough of time on your hands.
OpenOffice.
You can program against it and have it do a lot for you, without spending the money on a license for the server, or have the vulnerability associated with it on your server.
Microsoft Excel workbooks can be read using an ODBC driver (or is it an OLE DB driver? can't remember) that makes the workbook look like a database table. But I don't know whether that driver is available without the Office Suite itself.
You can use OpenOffice. It has a command-line conversion tool:
Conversion Howto
In short, you define a macro in OpenOffice and you call that macro with a command-line
argument to OpenOffice. In that argument the name of the local file (the Office file) is
encoded.
It's not a great sollution, but it should be workable.
I'm trying to create a Zip file from .Net that can be read from Java code.
I've used SharpZipLib to create the Zip file but also if the file generated is valid according to the CheckZip function of the #ZipLib library and can be successfully uncompressed via WinZip or WinRar I always get an error when trying to uncompress it using the Java.Utils.Zip class in Java.
Problem seems to be in the wrong header written by SharpZipLib, I've also posted a question on the SharpDevelop forum but with no results (see http://community.sharpdevelop.net/forums/t/8272.aspx for info) but with no result.
Has someone a code sample of compressing a Zip file with .Net and de-compressing it with the Java.Utils.Zip class?
Regards
Massimo
I have used DotNetZip library and it seems to work properly. Typical code:
using (ZipFile zipFile = new ZipFile())
{
zipFile.AddDirectory(sourceFolderPath);
zipFile.Save(archiveFolderName);
}
I had the same problem creating zips with SharpZipLib (latest version) and extracting with java.utils.zip.
Here is what fixed the problem for me. I had to force the exclusion of the zip64 usage:
ZipOutputStream s = new ZipOutputStream(File.Create(someZipFileName))
s.UseZip64 = UseZip64.Off;
Can't help with SharpZipLib, but you can try to create zip file using ZipPackage class System.IO.Packaging without using 3rd part libraries (requires .NET 3+).
To judge whether it's really a conformant ZIP file, see PKZIP's .ZIP File Format Specification.
For what it's worth I have had no trouble using SharpZipLib to create ZIPs on a Windows Mobile device and open them with WinZip or Windows XP's built-in Compressed Folders feature, and also no trouble producing ZIPs on the desktop with SharpZipLib and processing them with my own ZIP extraction utility (basically a wrapper around zlib) on the mobile device.
You don't wanna use the ZipPackage class in .NET - it isn't quite a standard zip model. Well it is, but it presumes a particular structure in the file, with a manifest with a well-known name, and so on. ZipPackage seems to have been optimized for Office docs and XPS docs.
A third-party library, like http://www.codeplex.com/DotNetZip, is probably a better bet if you are doing general-purpose ZIP files and want good interoperability.
DotNetZip builds files that are very interoperable with just about everything, including Java's java.utils.zip. But be careful using features that Java does not support, like ZIP64 or Unicode. ZIP64 is useful only for very large archives, which Java does not support well at this time, I think. Java supports Unicode in a particular way, so if you produce a Unicode-based ZIP file with DotNetZip, you just have to follow a few rules and it will work fine.
I had a similar problem with unzipping SharpZipLib-zipped files on Linux. I think I solved it (well I works on Linux and Mac now, I tested it), check out my blog post: http://igorbrejc.net/development/c/sharpziplib-making-it-work-for-linuxmac