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How to translate a lambda expression to normal code? c# [closed]

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I need to use this code in .net Framework 2.0 but the problem is that labmdas(WHERE) can't be used in this version, is there a way?
var serializer = new JavaScriptSerializer();
retorno = serializer.Deserialize<RespuestaCvt>(respuesta);
var soloServidores = retorno.Rows.Where(x => listaEstados.Contains(x.EstadoId)).Where(x => listaTipos.Contains(x.TipoId)).ToList();
return soloServidores;

Since Lambda expressions were not available until C# 3 you will have to change the way you do the actual row filtering. Since you're returning List<> we can just go back to the pre-LINQ way of doing things:
var soloServidores = new List<TheRowType>();
foreach (var row in retorno.Rows)
{
if (listaEstados.Contains(row.EstadoId) && listaTipos.Contains(x.TopiId))
soloServidores.Add(row);
}
return soloServidores;
Of course you could do it the hard way and extract the lambda to a static method then implement a suitable Where(...) extension... but if you're going to try to emulate C# features from a later language version then you're usually better off migrating your project to that later version.

Set field to true in JAVA [closed]

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Wasn't sure how to search for this and was unable to find the answer to set the following to true (Java):
boolean flagRefund = true;
if (flagRefund){
// Suppose to set wasRefunded field for user in DB to true or 1
dbModelUser.getWasRefunded();
}

This is a lesson to teach you how to read the code if you see the method that starts with "get" then you use it to get some value from the method that returns it. When the method starts with "set" then this method usually returns void and takes parameters. Like this
boolean flagRefund = true;
if (flagRefund){
// Suppose to set wasRefunded field for user in DB to true or 1
dbModelUser.setWasRefunded(flagRefund);
}

Usually, get methods are used to retrieve information, not to set information. Look if there is some set in your code method to achieve it.
Also, you don't pass any value to your method getWasRefunded as parameter so it is impossible that it could set any info.

I need a three-valued logic in Java [closed]

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I have tried to return null as third value in my boolean function, but it won't compile. I need to return three values from my class method - true, false and null (for example). Is there any standard way how can I do it?

Please use an enumeration with three values defined. Hacking things together is no solution.

Similar question has been asked, it should help.
You can make your own POJO object with this logic in getXX() method. From your method return this POJO with value and test it in code.
Generaly, don't use null values as state indicators.

Looking for an elegant way to convert a copy book in Swift in Java [closed]

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I'm doing a conversion from a COBOL copybook to a SWIFT message. First I'm parsing the copybook with a copybookHelper class and then I write a giant set of if statements to test all the fields and populate my SWIFT string. Is there a less cumbersome way to implement it (without the gigantic set of ifs)?
SWIFT = Society for Worldwide Interbank Financial Telecommunication

Would an Enum of the different message types help? With an enumeration in place, parsing a particular type and populating the swift string could be as simple as:
SwiftMessage msg = Enum.valueOf(SwiftMessage.class, "MT001");
msg.populateString(/* parameters? */);
An example of how you would write the enum implementation:
enum SwiftMessage {
MT001,
MT002 { void populateString() { /* override implementation */ } },
...
void populateString() { /* default implementation */ }
}
It's hard to be more specific without any details of what you are trying to do.

How to reverse the SingleLinkedList in the Java? [closed]

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Hi I want to print the SingleLinkedList in reverse.

static void Collections.reverse(List list):
http://download.oracle.com/javase/1.4.2/docs/api/java/util/Collections.html

See Collections.reverse (JavaDoc)

I don't know for "The SingleLinkedList" class (is it even a List implementation ?) but if it works as its name states, the best way (more effective one) would be to go through the data structure and put every element in a stack. Then simply read the stack.

public print(Element el) {
if (el.next!=null)
print(el.next);
System.out.print(el.value+" ");
}
Basicaly its puting it in (call) stack an reading it (as someone else sugested). Nonrecursive version using explicit stack is usualy faster, does not risk StackOverflowException and takes longer to write.