Nope - you said it yourself, static fields aren&#39;t serialized.

Kinda weird that the compiler lets you do that though.

In most cases, it is not useful. Static fields are indeed not serialized by the default serializer.

However, `static` `transient` fields can be detected via reflection. If someone writes its own serializer and he wants to also serialize static fields, then he *might* take the `transient` keyword in consideration and skip the serialization of that particular field.

*PS: This answer is posted for the sake of completeness, and is based on [Peter Lawrey&#39;s comment][1]. Credits to him.*


  [1]: https://stackoverflow.com/questions/4565653/java-static-transient-fields#comment5008564_4565653

I was wondering how to use a regexp to match a phrase that comes after a certain match. Like:

    var phrase = &quot;yesthisismyphrase=thisiswhatIwantmatched&quot;;
    var match = /phrase=.*/;

That will match from the `phrase=` to the end of the string, but **is it possible to get everything after the `phrase=` without having to modify a string**?

Javascript Regexp - Match Characters after a certain phrase

I have been trying to read up on 32-bit and 64-bit processors ([http://en.wikipedia.org/wiki/32-bit_processing][1]). My understanding is that a 32-bit processor (like x86) has registers 32-bits wide. I&#39;m not sure what that means. So it has special &quot;memory spaces&quot; that can store integer values up to 2^32?

I don&#39;t want to sound stupid, but I have no idea about processors. I&#39;m assuming 64-bits is, in general, better than 32-bits. Although my computer now (one year old, Win 7, Intel Atom) has a 32-bit processor. 


  [1]: http://en.wikipedia.org/wiki/32-bit_processing

What is the difference between a 32-bit and 64-bit processor?

I just found out in Java you can declare a field &#39;static transient&#39; - the compiler doesn&#39;t complain. This doesn&#39;t seem to be useful in any way since static fields are not serialized, as we all know.

But I wonder, is there actually a case where &#39;static transient&#39; fields are useful?

Java: Static transient fields

<p>I just found out in Java you can declare a field 'static transient' - the compiler doesn't complain. This doesn't seem to be useful in any way since static fields are not serialized, as we all know.</p>
<p>But I wonder, is there actually a case where 'static transient' fields are useful?</p>


Maven `dependency:analyze` complains about the dependencies in my project. How does it determine which are unused and which are undeclared? What should I do about them?

Example:

    $ mvn dependency:analyze 
    ...
    [WARNING] Used undeclared dependencies found:
    [WARNING]    org.slf4j:slf4j-api:jar:1.5.0:provided
    [WARNING]    commons-logging:commons-logging:jar:1.1.1:compile
    [WARNING]    commons-dbutils:commons-dbutils:jar:1.1-osgi:provided
    [WARNING]    org.codehaus.jackson:jackson-core-asl:jar:1.6.1:compile

    ...
    [WARNING] Unused declared dependencies found:
    [WARNING]    commons-cli:commons-cli:jar:1.0:compile
    [WARNING]    org.mortbay.jetty:servlet-api:jar:2.5-20081211:test
    [WARNING]    org.apache.httpcomponents:httpclient:jar:4.0-alpha4:compile
    [WARNING]    commons-collections:commons-collections:jar:3.2:provided
    [WARNING]    javax.mail:mail:jar:1.4:provided


Note:
A lot of these dependencies are used in my runtime container and I declared them as provided to avoid having the same library on the classpath twice with different versions. 


What are unused/undeclared dependencies in Maven? What to do with them?

**Code:**

    public class Test {
    	public static void main(String[] args) {
    		String str = &quot;University&quot;;
    		System.out.println(str.substring(4, 7));
    	}	
    }

**Output:** `ers`

I do not really understand how the substring method works. Does the index start at 0? If I start with 0, `e` is at index 4 but char `i` is at 7 so the output would be `ersi`.


substring index range

Suddenly this keeps happening during a JUnit test. Everything was working, I wrote some new tests and this error occured. If I revert it, it won&#39;t go away. Why is that?

    log4j:WARN No appenders could be found for logger (org.springframework.test.context.junit4.SpringJUnit4ClassRunner).
    log4j:WARN Please initialize the log4j system properly.
    log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.


How to configure log4j.properties for SpringJUnit4ClassRunner?

I&#39;d like to add a progress indicator to a command-line Java program.

For example, if I&#39;m using wget, it shows:

    71% [===========================&gt;           ] 358,756,352 51.2M/s  eta 3s

Is it possible to have a progress indicator that updates without adding a new line to the bottom?

Thanks.

Java: Updating text in the command-line without a new line

For a new project is JPA always the recommended tool for handling relational data or are there scenarios where Spring JdbcTemplate is a better choice? Some factors to consider in your response:

 - new database schema vs pre-existing schema and tables
 - level of developer expertise
 - ease with which can integrate with a data caching layer
 - performance
 - any other relevant factors to consider?

 





JPA vs Spring JdbcTemplate

I have a `JsonResult` that is working fine, and returning JSON from some POCO&#39;s. I want to save the JSON as a string in a DB.     

    public JsonResult GetJSON()
    {
        JsonResult json = new JsonResult
        {
            Data = GetSomPocos()
        }; 
        return json;
    }

I need to audit the response, so I want to save the `json` into a DB. I am having trouble finding a way to get the JSON as a string.

Any help is appreciated.

JSONResult to String

The only way that my WCF service can return classes from a code first model is by setting the `ProxyCreationEnable` to `false` using the code below.

    ((IObjectContextAdapter)MyDb).ObjectContext.ContextOptions.ProxyCreationEnable = false;

What are the negative consequences of doing this?  One gain is that I can at least get these dynamic types serialized so they can be sent over the wire using WCF.

What are the downsides to turning off ProxyCreationEnabled for CTP5 of EF code first

It seems by default disabled input elements are ignored by `$.serialize()`. Is there a workaround?


How do I make $.serialize() take into account those disabled :input elements?

I&#39;m trying to learn Gson and I&#39;m struggling with field exclusion. Here are my classes

    public class Student {    
      private Long                id;
      private String              firstName        = &quot;Philip&quot;;
      private String              middleName       = &quot;J.&quot;;
      private String              initials         = &quot;P.F&quot;;
      private String              lastName         = &quot;Fry&quot;;
      private Country             country;
      private Country             countryOfBirth;
    }
    
    public class Country {    
      private Long                id;
      private String              name;
      private Object              other;
    }

I can use the GsonBuilder and add an ExclusionStrategy for a field name like `firstName` or `country` but I can&#39;t seem to manage to exclude properties of certain fields like `country.name`.

Using the method `public boolean shouldSkipField(FieldAttributes fa)`, FieldAttributes doesn&#39;t contain enough information to match the field with a filter like `country.name`.

P.S: I want to avoid annotations since I want to improve on this and use RegEx to filter fields out.

**Edit**: I&#39;m trying to see if it&#39;s possible to emulate the behavior of [Struts2 JSON plugin][1]


  [1]: https://cwiki.apache.org/confluence/display/WW/JSON%20Plugin 
using Gson

    &lt;interceptor-ref name=&quot;json&quot;&gt;
      &lt;param name=&quot;enableSMD&quot;&gt;true&lt;/param&gt;
      &lt;param name=&quot;excludeProperties&quot;&gt;
        login.password,
        studentList.*\.sin
      &lt;/param&gt;
    &lt;/interceptor-ref&gt;

**Edit:**
    I reopened the question with the following addition:

I added a second field with the same type to futher clarify this problem. Basically I want to exclude `country.name` but not `countrOfBirth.name`. I also don&#39;t want to exclude Country as a type.
So the types are the same it&#39;s the actual place in the object graph that I want to pinpoint and exclude.

Gson: How to exclude specific fields from Serialization without annotations

Is it possible to serialize a .Net Dictionary&amp;lt;Key,Value&amp;gt; into JSON with **DataContractJsonSerializer** that is of the format:

    {
      key0:value0,
      key1:value1,
      ...
    }

I use Dictionary &amp;lt;K,V&amp;gt;, because there is not predefined structure of the inputs.

I&#39;m interesting just for **DataContractJsonSerializer** result! I&#39;ve already found a &quot;Surrogate&quot; example, but there is an additional &quot;data&quot; in the output, and if the dictionary &amp;lt;K, String&amp;gt; is, the escaping is false too.

-------------------------
I&#39;ve found the solution, what a needed! First of all, a serializable &quot;dictionary&quot; class:
(Of course, this sample works just in one way, but I dont&#39;t need deserialization)

	[Serializable]
	public class MyJsonDictionary&lt;K, V&gt; : ISerializable {
		Dictionary&lt;K, V&gt; dict = new Dictionary&lt;K, V&gt;();
		
		public MyJsonDictionary() { }

		protected MyJsonDictionary( SerializationInfo info, StreamingContext context ) {
			throw new NotImplementedException();
		}

		public void GetObjectData( SerializationInfo info, StreamingContext context ) {
			foreach( K key in dict.Keys ) {
				info.AddValue( key.ToString(), dict[ key ] );
			}
		}

		public void Add( K key, V value ) {
			dict.Add( key, value );
		}
		
		public V this[ K index ] {
			set { dict[ index ] = value; }
			get { return dict[ index ]; }
		}
	}

Usage:

    public class MainClass {
		public static String Serialize( Object data ) {
			var serializer = new DataContractJsonSerializer( data.GetType() );
			var ms = new MemoryStream();
			serializer.WriteObject( ms, data );

			return Encoding.UTF8.GetString( ms.ToArray() );
		}

		public static void Main() {
			MyJsonDictionary&lt;String, Object&gt; result = new MyJsonDictionary&lt;String, Object&gt;();
			result[&quot;foo&quot;] = &quot;bar&quot;;
			result[&quot;Name&quot;] = &quot;John Doe&quot;;
			result[&quot;Age&quot;] = 32;
			MyJsonDictionary&lt;String, Object&gt; address = new MyJsonDictionary&lt;String, Object&gt;();
			result[&quot;Address&quot;] = address;
			address[&quot;Street&quot;] = &quot;30 Rockefeller Plaza&quot;;
			address[&quot;City&quot;] = &quot;New York City&quot;;
			address[&quot;State&quot;] = &quot;NY&quot;;

			Console.WriteLine( Serialize( result ) );

			Console.ReadLine();
		}
	}

And the result:

    {
          &quot;foo&quot;:&quot;bar&quot;,
          &quot;Name&quot;:&quot;John Doe&quot;,
          &quot;Age&quot;:32,
          &quot;Address&quot;:{
             &quot;__type&quot;:&quot;MyJsonDictionaryOfstringanyType:#Json_Dictionary_Test&quot;,
             &quot;Street&quot;:&quot;30 Rockefeller Plaza&quot;,
             &quot;City&quot;:&quot;New York City&quot;,
             &quot;State&quot;:&quot;NY&quot;
          }
       }

C# JSON Serialization of Dictionary into {key:value, ...} instead of {key:key, value:value, ...}

Hi I&#39;m trying to declar a static enum like so:


   

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    
    namespace Lds.CM.MyApp.Controllers
    {
        public class MenuBarsController : Controller
        {
            // Menu Bar enums
            public static enum ProfileMenuBarTab { MainProfile, Edit, photoGallery }
    
            public ActionResult cpTopMenuBar(string tabSelected)
            {
                ...            
&quot;
But I&#39;m getting the following error:  &quot;The modifier &#39;static&#39; is not valid for this item.&quot;
I know it&#39;s something simple but I can&#39;t seem to see the problem.  Much thanks!

troubles declaring static enum, C#

In C++ it is possible to use the `static` keyword within a translation unit to affect the visibility of a symbol (either variable or function declaration).

In n3092, this was deprecated:

&gt; Annex D.2 **[depr.static]**  
&gt; The use of the static keyword is deprecated when declaring objects in namespace scope (see 3.3.6).

In n3225, this has been removed.

The [only article I could find][1] is somewhat informal.

It does underline though, that for compatibility with C (and the ability to compile C-programs as C++) the deprecation is annoying. However, compiling a C program directly as C++ can be a frustrating experience already, so I am unsure if it warrants consideration.

Does anyone know why it was changed ?


  [1]: https://web.archive.org/web/20140116013834/http://www.informit.com/guides/content.aspx?g=cplusplus&amp;seqNum=463

Deprecation of the static keyword... no more?

I just start out with an example, that explains it best:

    public abstract class A{
    	static String str;
    }

    public class B extends A{
    	public B(){
    		str = &quot;123&quot;;
    	}
    }

    public class C extends A{
    	public C(){
    		str = &quot;abc&quot;;
    	}
    }

    public class Main{
    
    	public static void main(String[] args){
    		A b = new B();
    		A c = new C();
    		System.out.println(&quot;b.str = &quot; + b.str);
    		System.out.println(&quot;c.str = &quot; + c.str);
    	}
    }

This will print out:

b.str = abc

c.str = abc


But I would like a solution where each subclass that instantiate the super class, has their **own** class variable, at the same time I want to be able to reference that class variable through the identifier, or a method call, defined in the abstract super class.

So I would like the output to be: 

b.str = 123 

c.str = abc

Is that doable? 



Java: static field in abstract class

I have a class named `Media` which has a method named `setLoanItem`:

    public void setLoanItem(String loan) {
        this.onloan = loan;
    }

I am trying to call this method from a class named `GUI` in the following way:

    public void loanItem() {
        Media.setLoanItem(&quot;Yes&quot;);
    }

But I am getting the error 

&gt; non-static method setLoanItem(java.lang.String) cannot be referenced from a static context

I am simply trying to change the variable `onloan` in the `Media` class to &quot;Yes&quot; from the `GUI` class.

I have looked at other topics with the same error message but nothing is clicking!

&quot;Non-static method cannot be referenced from a static context&quot; error

My teacher in an upper level Java class on threading said something that I wasn&#39;t sure of.

He stated that the following code would not necessarily update the `ready` variable.  According to him, the two threads don&#39;t necessarily share the static variable, specifically in the case when each thread (main thread versus `ReaderThread`) is running on its own processor and therefore doesn&#39;t share the same registers/cache/etc and one CPU won&#39;t update the other.

Essentially, he said it is possible that `ready` is updated in the main thread, but NOT in the `ReaderThread`, so that `ReaderThread` will loop infinitely.

He also claimed it was possible for the program to print `0` or `42`.  I understand how `42` could be printed, but not `0`.  He mentioned this would be the case when the `number` variable is set to the default value.

I thought perhaps it is not guaranteed that the static variable is updated between the threads, but this strikes me as very odd for Java.  Does making `ready` volatile correct this problem?

He showed this code:  

    public class NoVisibility {  
        private static boolean ready;  
        private static int number;  
        private static class ReaderThread extends Thread {   
            public void run() {  
                while (!ready)   Thread.yield();  
                System.out.println(number);  
            }  
        }  
        public static void main(String[] args) {  
            new ReaderThread().start();  
            number = 42;  
            ready = true;  
        }  
    }


Are static variables shared between threads?

is there a way to disable all fields (textarea/textfield/option/input/checkbox/submit etc) in a form by telling only the parent div name in jquery/javascript?

disable all form elements inside div

what is the right field type for IP address in mysql? and what is the right way of storing it using PHP?

IP address storing in MySQL database using PHP

I have a hidden text field whose value gets updated via an AJAX response.

    &lt;input type=&quot;hidden&quot; value=&quot;&quot; name=&quot;userid&quot; id=&quot;useid&quot; /&gt;

When this value changes, I would like to fire an AJAX request. Can anyone advise on how to detect the change?

I have the following code, but do not know how to look for the value:

    $(&#39;#userid&#39;).change( function() {  
       	alert(&#39;Change!&#39;); 
    }) 

jQuery - Detect value change on hidden input field

I looked through the MongoDB documentation and googled this question but couldn&#39;t really find a suitable answer. So, here is what I&#39;m looking for. 
Assume I have a collection with elements like this:

    {
       &quot;foo&quot; : &quot;bar&quot;,
       &quot;test&quot; : &quot;test&quot;,
       &quot;key&quot; : &quot;value&quot;,
    }

What I&#39;d like to achieve is find an element by searching in all (maybe except for finitely many ;-) ) fields. In other words: Given a query, I do NOT know in which field the query should be found.

In my thinking something like this 

    db.things.find({_ANY_ : &quot;bar&quot;}) 

would give me the example element.

Thank you for your help.

Searching for value of any field in MongoDB without explicitly naming it

I have a table with two fields (countries and ISO codes):

    Table1
    
       field1 - e.g. &#39;Afghanistan&#39; (without quotes)
       field2 - e.g. &#39;AF&#39;(without quotes)


In some rows the second field has whitespace at the start and/or end, which is affecting queries. 

    Table1
    
       field1 - e.g. &#39;Afghanistan&#39; (without quotes) 
       field2 - e.g. &#39; AF&#39; (without quotes but with that space in front)

Is there a way (in SQL) to go through the table and find/replace the whitespace in field2?


How to remove leading and trailing whitespace in a MySQL field?

I saw somewhere
&lt;pre&gt;
&lt;code&gt;
transient private TrackDAO trackDAO;
&lt;/code&gt;
&lt;/pre&gt;

What does the keyword &quot;transient&quot; mean in Java?

I just want to know what is the difference between all these annotations. Why are we using these... means they have no effect especially field level and property level.

And what is the purpose of using mixed level annotation like:

    @Entity
    @Access(AccessType.FIELD)
    class Employee {
        // why their is a field level access 
        private int id;
     
        // whats the purpose of transient here
        @Transient                               
        private String phnnumber;
     
        // why its a property level access
        @Access(AccessType.property)             
        public String getPhnnumber() {
            return &quot;1234556&quot;;
        }

    }


what exactly this class says?

Content Type	Original Author	Original Content on Stackoverflow
Question	python dude	View Question on Stackoverflow
Solution 1 - Java	Peter C	View Answer on Stackoverflow
Solution 2 - Java	MC Emperor	View Answer on Stackoverflow

Java: Static transient fields

Java Problem Overview

Java Solutions

Solution 1 - Java

Solution 2 - Java

What is the difference between a 32-bit and 64-bit processor?

Javascript Regexp - Match Characters after a certain phrase

Attributions