I am working on an add-on component that needs to play nice with other similar add-ons. There is a 3rd party component that decided to implement the functionality a little differently than the default.
What I am trying to do is call an overload of a method that only the 3rd party component has, like this:
Select Case True
Case TypeOf provider Is 3rdParty.Provider
result = DirectCast(provider, 3rdParty.Provider).GetNames(method, True)
Case Else
result = provider.GetNames(method)
End Select
Unfortunately, the DLL that contains 3rdParty.Provider is optional, so this code will give compile errors if it is not present. How can I accomplish the same thing but make it safe to run whether the 3rdParty.Provider.dll is present or not?
You need inversion of control for this.
Check Castle Windsor or Microsoft Unity projects.
These will provide you a way to switch implementations of same base type by configuration.
http://www.castleproject.org/container/
http://unity.codeplex.com/
After some trial and error and going through several MSDN docs and forum posts, I was able to piece together the following solution:
Dim t As Type = Type.GetType("3rdParty.Provider, 3rdParty.Provider")
Select Case True
Case Object.ReferenceEquals(provider.GetType(), t)
result = Convert.ChangeType(provider, t).GetNames(method, True)
Case Else
result = provider.GetNames(method)
End Select
I tested removing the 3rd party DLL reference from my project and this works without a hitch and calls the default GetNames in that case without any exceptions or compile errors.
Related
I have an enumerand of around 150 entries, which I need to get into IBM Rhapsody.
Doing this by hand is clearly lengthy and error prone. I have google extensively but found only things that tell me how to edit the generated code -- not go the other way.
The question is: How is this done? And if there is no way -- please someone post that as an answer.
David,
I would jump into the Java API (plugin subsystem) and do it that way. If you haven't learned how to use the API, there is a bit of a learning curve. There are two ways to go about it: Implement a Java (or your favorite JVM language--I use Scala) app that realizes the Rhapsody Plugin framework and then you choose to package it up and deploy it so that it gets loaded when you load your model, or, if it is a one off job, do everything up to the point of packaging it up and then run it from within your IDE and you are done. If you are comfortable with Scala, I can post some code.
So what I did in the end was I edited the relevant .sbs file, used a small python program to generate the items I required, and then update the length of the array accordingly.
all_the_literals = ["enum_name = 0x4e", enum_name2 = 0xF2", ... ,]
for field1, waste, field1_value in map(lambda x: x.split(" "),
all_the_literals):
literal_string = f""" {{ IEnumerationLiteral
- _id = GUID {uuid.uuid4()};
- _name = \"{field1}\";
- codeUpdateCGTime = 5.16.2022::19:24:18;
- _modifiedTimeWeak = 5.16.2022::19:24:18;
- _value = \"{field1_value}\";
}}"""
print(literal_string)
Note the above "code" snippet purely prints the items, which you then copy-paste into the relevant field in the sbs file. YMMV -- this was the correct format for an enum in Rhapsody (and note how I fudged the update time, but it worked successfully, so you'll need to do the same if you use this answer).
Also note it's probably better to use bauhaus9's answer, but I definitely didn't have time for it.
I am working on SQLite File Encryption. I have added sqlCipher & crypto frameworks successfully in my project.
Now when I try to compile my application on this line
int rc = sqlite3_key(database, [key UTF8String], strlen([key UTF8String]));
it says Implicit declaration of function 'sqlite3_key'
So above line "implicit declaration" sounds to me like function is defined but not declared. But where I have to declared ?
While searching over Internet, under this article, it says like SQLite Encryption Extension(SEE) is not available publically. I have to purchase it of cost around $2000.
SEE -> http://www.hwaci.com/sw/sqlite/see.html
So this is the only reason I am getting Implicit declaration & False response while sqlite encryption process ?
If you are using SQLCipher, you need to define SQLITE_HAS_CODEC in your application's C Flags. Thats all.
Yes, that is the reason you are getting that compiler warning. The function sqlite3_key() is not defined in the version of libsqlite3 included with iOS. Adding in a function declaration isn't going to help-- it would fix that compiler warning, but it would just mean you'll get a linker error since the function isn't defined anywhere.
If you purchased SEE you could probably build your own copy of SQLite, embed it in your app, and just not use the system's libsqlite3. That this would mean you'd have to say "yes" when the app store submission process asks if your app includes encryption, meaning extra paperwork and time before you could submit the app. I'm not certain whether there's any clear indication of whether Apple would accept it even then-- probably they would, but they've been known to surprise people.
Two questions
How to check file exists or not before EXTRACT?
we have scenario where new inputs file is generated every day for catalog data. we need to merge new input with d-1 file. before merge we what to make sure that new input file exists at source location
does u-sql supports try...catch block?
Regarding checking if a file exists. We recently released a compile-time IF statement that indeed can check for partition existence (and other objects such as files and tables are on the roadmap).
Once that feature is released (still one or two refreshs out at the time of this answer) it may look something like (syntax subject to change):
IF FILE.EXISTS("/mydir/myfile.csv") THEN
#data = EXTRACT ... FROM "/mydir/myfile.csv" USING ...;
...
#jobstate = SELECT * FROM (VALUES("job completed")) AS T(status);
ELSE
#jobstate = SELECT * FROM (VALUES("file not ready. Job not executed.")) AS T(status);
END;
OUTPUT #jobstate TO "/jobs/myjobstate.csv" USING Outputters.Csv();
You will be able to provide the name as a parameter as well. Please let me know if that will work for your scenario.
An other alternative is to use the file set syntax, especially if you want to use a dynamic value to determine the process. That would simply create an empty rowset:
#data = EXTRACT ..., date DateTime
FROM "/mydir/{date:yyyy}/{date:MM}/{date:dd}/data.csv"
USING ...;
#data = SELECT * FROM #data WHERE date == DateTime.Now.AddDays(-1);
... // continue processing #data that is empty if yesterday's file is not yet there
Having said that, you may want to check of your job orchestration framework (such as ADF) may be a better place to check for existence before submitting the job in the first place.
As to the try catch block: U-SQL itself is a script-level optimizable, declarative language where the plan gets generated and optimized at runtime over the whole script. Thus providing a dynamic TRY-CATCH is currently not available, since it would severely impact the ability to optimize the script (e.g., you cannot move predicates or column pruning outside of a try-catch block). Also TRY/CATCH can lead to some very hard to understand and debug code, especially if it is used to mimic procedural workflows in an otherwise declarative environment.
However, you can use try/catch inside your C# functions without problems if you need to catch C# runtime errors.
FILE.EXISTS() always returns True when executed locally. However, it works when executing against Azure Data Lake.
Tried MSDN example and the following returns True, True
DECLARE #filepath_good = "/Samples/Data/SearchLog.tsv";
DECLARE #filepath_bad = "/Samples/Data/zzz.tsv";
#result =
SELECT FILE.EXISTS(#filepath_good) AS exists_good,
FILE.EXISTS(#filepath_bad) AS exists_bad
FROM (VALUES (1)) AS T(dummy);
OUTPUT #result
TO "/Output/FileExists.txt"
USING Outputters.Csv();
I have Microsoft Azure Data Lake Tools for Visual Studio version 2.2.5000.0
In roboelectric when you write your test class you have declare the #RunWith annotation of which there is RobolectricGradleTestRunner and RobolectricTestRunner.class. What is the difference and which one should we use ? Why is there 2 in the first place. If I use RobolectricTestRunner then it does not work for me it says some weird error like :
"java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity."
However this seems to go away if I use RobolectricGradleTestRunner.
RobolectricTestRunner was first and is for maven based projects.
RobolectricGradleTestRunner was for gradle based projects because some paths have changed.
Since robolectric 3.1.1 this is not more necessary and is now deprecated.
For more details see also http://robolectric.org/getting-started/
I'd like to analyze .Net assemblies to be language independent from C#, VB.NET or whatever.
I know Roslyn and NRefactory but they only seem to work on C# source code level?
There is also the "Common Compiler Infrastructure: Code Model and AST API" project on CodePlex which claims to "supports a hierarchical object model that represents code blocks in a language-independent structured form" which sound exactly for what I looking for.
However I'am unable to find any useful documentation or code that is actual doing this.
Any advice how to archive this?
Can Mono.Cecil maybe doing something?
You can do this and there is also one (although tiny) example of this in the source of ILSpy.
var assembly = AssemblyDefinition.ReadAssembly("path/to/assembly.dll");
var astBuilder = new AstBuilder(new DecompilerContext(assembly.MainModule));
decompiler.AddAssembly(assembly);
astBuilder.SyntaxTree...
The CCI Code Model is somewhere between a IL disassembler and full C# decompiler: it gives your code some structure (e.g. if statements and expressions), but it also contains some low level stack operations like push and pop.
CCI contains a sample that shows this: PeToText.
For example, to get Code Model for the first method of the Program type (in the global namespace), you could use code like this:
string fileName = "whatever.exe";
using (var host = new PeReader.DefaultHost())
{
var module = (IModule)host.LoadUnitFrom(fileName);
var type = (ITypeDefinition)module.UnitNamespaceRoot.Members
.Single(m => m.Name.Value == "Program");
var method = (IMethodDefinition)type.Members.First();
var methodBody = new SourceMethodBody(method.Body, host, null, null);
}
To demonstrate, if you decompile the above code and show it using PeToText, you're going to get:
Microsoft.Cci.ITypeDefinition local_3;
Microsoft.Cci.ILToCodeModel.SourceMethodBody local_5;
string local_0 = "C:\\code\\tmp\\nuget tmp 2015\\bin\\Debug\\nuget tmp 2015.exe";
Microsoft.Cci.PeReader.DefaultHost local_1 = new Microsoft.Cci.PeReader.DefaultHost();
try
{
push (Microsoft.Cci.IModule)local_1.LoadUnitFrom(local_0).UnitNamespaceRoot.Members;
push Program.<>c.<>9__0_0;
if (dup == default(System.Func<Microsoft.Cci.INamespaceMember, bool>))
{
pop;
push Program.<>c.<>9.<Main0>b__0_0;
Program.<>c.<>9__0_0 = dup;
}
local_3 = (Microsoft.Cci.ITypeDefinition)System.Linq.Enumerable.Single<Microsoft.Cci.INamespaceMember>(pop, pop);
local_5 = new Microsoft.Cci.ILToCodeModel.SourceMethodBody((Microsoft.Cci.IMethodDefinition)System.Linq.Enumerable.First<Microsoft.Cci.ITypeDefinitionMember>(local_3.Members).Body, local_1, (Microsoft.Cci.ISourceLocationProvider)null, (Microsoft.Cci.ILocalScopeProvider)null, 0);
}
finally
{
if (local_1 != default(Microsoft.Cci.PeReader.DefaultHost))
{
local_1.Dispose();
}
}
Of note are all those push, pop and dup statements and the lambda caching condition.
As far as I know, it's not possible to build AST from binary (without sources) since AST itself generated by parser as part of compilation process from sources.
Mono.Cecil won't help because you can only modify opcodes/metadata with them, not analyze assembly.
But since it's .NET you can dump IL code from dll with help of ildasm. Then you can pass generated sources to any parser with CIL dictionary hooked up and get AST from parser. The problem is that as far as I know there is only one publically available CIL grammar for parser, so you don't really have a choice. And ECMA-355 is big enough so it's bad idea to write your own grammar.
So I can suggest you only one solution:
Pass assembly to ildasm.exe to get CIL.
Then pass CIL to ANTLR v3 parser with this CIL grammar wired up (note it's a little bit outdated - grammar created at 2004 and latest CIL specification is 2006, but CIL doesn't really change to much)
After that you can freely access AST generated by ANTLR
Note that you will need ANTLR v3 not v4, since grammar written for 3rd version, and it's hardly possible to port it to v4 without good knowledge of ANTLR syntax.
Also you can try to look into new Microsoft ryujit compiler sources at github (part of CoreCLR) - I don't sure that it's helps, but in theory it must contains CIL grammar and parser implementations since it works with CIL code. But it's written in CPP, have enormous code base and lacks of documentation since it's in active development stage, so it's may be easier to stuck with ANTLR.
If you treat the .net binary file as a stream of bytes, you ought to be able to "parse" it just fine.
You simply write a grammar whose tokens are essentially bytes. You can certainly build a classical lexer/parser with almost any set of lexer/parser tools by defining the lexer to read single bytes as tokens.
You can then build the AST using standard AST-building machinery for the parsing engine (on your own for YACC, automatically with ANTLR4).
What you will discover, of course, is that "parsing" isn't enough; you'll still need to build symbol tables, and carry out control and data flow analyses if you are going to do serious analysis of the corresponding code. See my essay on LifeAfterParsing.
You will also likely have to take into account "distinguished" functions that provide key runtime facilities to the particular programming languages that actually generated the CIL code. And these will make your analyzers language-dependent. Yes, you still get to share the part of the analysis that works on generic CIL.