Use [`ByteArrayInputStream`][1]:

    InputStream is = new ByteArrayInputStream(decodedBytes);


  [1]: http://docs.oracle.com/javase/8/docs/api/java/io/ByteArrayInputStream.html

If you use [Robert Harder&#39;s Base64 utility][1], then you can do:

    InputStream is = new Base64.InputStream(cph);

Or with sun&#39;s JRE, you can do:

    InputStream is = new
    com.sun.xml.internal.messaging.saaj.packaging.mime.util.BASE64DecoderStream(cph)

However don&#39;t rely on that class continuing to be a part of the JRE, or even continuing to do what it seems to do today. Sun say not to use it.

There are other Stack Overflow questions about Base64 decoding, such as [this one.][2] 


  [1]: http://iharder.sourceforge.net/current/java/base64/
  [2]: https://stackoverflow.com/questions/469695/decode-base64-data-in-java

I&#39;d like to have my array items scrambled.
Something like this:

    [1,2,3,4].scramble =&gt; [2,1,3,4]
    [1,2,3,4].scramble =&gt; [3,1,2,4]
    [1,2,3,4].scramble =&gt; [4,2,3,1]

and so on, randomly

How to randomly sort (scramble) an array in Ruby?

I&#39;d like to declare an &quot;empty&quot; lambda expression that does, well, nothing.
Is there a way to do something like this without needing the `DoNothing()` method?

    public MyViewModel()
    {
        SomeMenuCommand = new RelayCommand(
                x =&gt; DoNothing(),
                x =&gt; CanSomeMenuCommandExecute());
    }

    private void DoNothing()
    {
    }

    private bool CanSomeMenuCommandExecute()
    {
        // this depends on my mood
    }

My intent in doing this is only control the enabled/disabled state of my WPF command, but that&#39;s an aside. Maybe it&#39;s just too early in the morning for me, but I imagine there must be a way to just declare the `x =&gt; DoNothing()` lambda expression in some way like this to accomplish the same thing:

    SomeMenuCommand = new RelayCommand(
        x =&gt; (),
        x =&gt; CanSomeMenuCommandExecute());

Is there some way to do this? It just seems unnecessary to need a do-nothing method.

Is there a way to specify an &quot;empty&quot; C# lambda expression?

Can we convert a byte array into an InputStream in Java? I have been looking on the internet but couldn&#39;t find it.

I have a method that has an InputStream as argument.

The InputStream `cph` I have is base64 encoded so I had to decode it using

    BASE64Decoder decoder = new BASE64Decoder();
    byte[] decodedBytes = decoder.decodeBuffer(cph);

Now how do I convert `decodedBytes` again to `InputStream`?

Can we convert a byte array into an InputStream in Java?

Can we convert a byte array into an InputStream in Java? I have been looking on the internet but couldn't find it.
I have a method that has an InputStream as argument.
The InputStream <code>cph</code> I have is base64 encoded so I had to decode it using
<pre><code class="hljs language-ini">BASE64Decoder decoder = new BASE64Decoder();
byte[] decodedBytes = decoder.decodeBuffer(cph);
</code></pre>
Now how do I convert <code>decodedBytes</code> again to <code>InputStream</code>?

I have a question about simplifying some Collection handling code, when using Google Collections (*update*: [Guava][1]).

I&#39;ve got a bunch of &quot;Computer&quot; objects, and I want to end up with a Collection of their &quot;resource id&quot;s.  This is done like so:

    Collection&lt;Computer&gt; matchingComputers = findComputers();
    Collection&lt;String&gt; resourceIds = 
        Lists.newArrayList(Iterables.transform(matchingComputers, new Function&lt;Computer, String&gt;() {
        public String apply(Computer from) {
            return from.getResourceId();
        }
    }));


Now, `getResourceId()` may return null (and changing that is not an option right now), yet in this case I&#39;d like to omit nulls from the resulting String collection.

Here&#39;s one way to filter nulls out: 

    Collections2.filter(resourceIds, new Predicate&lt;String&gt;() {
        @Override
        public boolean apply(String input) {
            return input != null;
        }
    });

You could put all that together like this:

    Collection&lt;String&gt; resourceIds = Collections2.filter(
    Lists.newArrayList(Iterables.transform(matchingComputers, new Function&lt;Computer, String&gt;() {
        public String apply(Computer from) {
            return from.getResourceId();
        }
    })), new Predicate&lt;String&gt;() {
        @Override
        public boolean apply(String input) {
            return input != null;
        }
    });

But this is hardly elegant, let alone readable, for such a simple task! In fact, plain old Java code (with no fancy Predicate or Function stuff at all) would arguably be much cleaner:

    Collection&lt;String&gt; resourceIds = Lists.newArrayList();
    for (Computer computer : matchingComputers) {
        String resourceId = computer.getResourceId();
        if (resourceId != null) {
            resourceIds.add(resourceId);
        }
    }

Using the above is certainly also an option, but out of curiosity (and desire to learn more of Google Collections), **can you do the exact same thing in some shorter or more elegant way using Google Collections**?


  [1]: https://code.google.com/p/guava-libraries/

Is there an elegant way to remove nulls while transforming a Collection using Guava?

Java&#39;s [WeakHashMap][1] is often cited as being useful for caching. It seems odd though that its weak references are defined in terms of the map&#39;s keys, not its values. I mean, it&#39;s the values I want to cache, and which I want to get garbage collected once no-one else besides the cache is strongly referencing them, no?

In which way does it help to hold weak references to the keys? If you do a `ExpensiveObject o = weakHashMap.get(&quot;some_key&quot;)`, then I want the cache to hold on to &#39;o&#39; until the caller doesn&#39;t hold the strong reference anymore, and I don&#39;t care at all about the string object &quot;some_key&quot;.

Am I missing something?


  [1]: http://developer.android.com/reference/java/util/WeakHashMap.html

Java&#39;s WeakHashMap and caching: Why is it referencing the keys, not the values?

I did check the other questions; this question has its focus on solving this particular question the most efficient way. 

Sometimes you want to create a new string with a specified length, and with a default character filling the entire string.

ie, it would be cool if you could do `new String(10, &#39;*&#39;)` and create a new String from there, with a length of 10 characters all having a *.

Because such a constructor does not exist, and you cannot extend from String, you have either to create a wrapper class or a method to do this for you.

At this moment I am using this:

    protected String getStringWithLengthAndFilledWithCharacter(int length, char charToFill) {
        char[] array = new char[length];
        int pos = 0;
        while (pos &lt; length) {
            array[pos] = charToFill;
            pos++;
        }
        return new String(array);
    }

It still lacks any checking (ie, when length is 0 it will not work). I am constructing the array first because I believe it is faster than using string concatination or using a StringBuffer to do so.

Anyone else has a better sollution?

Java - Create a new String instance with specified length and filled with specific character. Best solution?

I tried using this but didn&#39;t work-

    return value.replaceAll(&quot;/[^A-Za-z0-9 ]/&quot;, &quot;&quot;);

Replacing all non-alphanumeric characters with empty strings

I wonder not only what is Facet but also what is Facet &#39;in physical level&#39; (as I understand it&#39;s not a separate jar, but what?)?

I also wonder how can it affect my application after deploying. I&#39;ll explain on real example:

I had 2 facets (which were created by IDE): Spring Facet and Web Facet (for jsf). I deployed it to Tomcat and my application worked fine.

Then I added (by means of IDE) one more facet - JPA Facet. I redeployed application and.. it still worked fine :) 

So, I&#39;m just curious what is that and why do we need it?

What is &#39;Facet&#39; in JavaEE?

Today I tried including the apache.commons.codec package in my Android application and couldn&#39;t get it running. Android could not find method ord.apache.commons.codec.binary.* and output the following errors in DDMS

&gt; 
01-12 08:41:48.161: ERROR/dalvikvm(457): Could not find method org.apache.commons.codec.binary.Base64.encodeBase64URLSafeString, referenced from method com.dqminh.app.util.Util.sendRequest
&gt;
01-12 08:41:48.161: WARN/dalvikvm(457): VFY: unable to resolve static method 10146: Lorg/apache/commons/codec/binary/Base64;.encodeBase64URLSafeString ([B)Ljava/lang/String;
&gt;
01-12 08:41:48.161: WARN/dalvikvm(457): VFY:  rejecting opcode 0x71 at 0x0004

Any clue on how to solve this problem ? Thanks a lot.





Apache Commons Codec with Android: could not find method

nvarchar(max), varchar(max), or should I really decode the string and put it in an image or blob or something?

### The longer version : (with all the juicy details) ###

I&#39;ve got a .Net SOAP web service, which saves records in a SQL 2008 DB. The service is going to be extended to accept an image, which (for better or worse) also needs to go into the DB temporarily.

To keep things simple, the service takes the image as a Base 64 encoded string, and will have to give it back as a base64 encoded string later (a different method on the same service).

I was originally just going to use nvarchar(max), and I&#39;m sure this would work. But then I thought that base64 encoded means it could use varchar(max) instead, and use less storage space. Is this right? Or should I bite the bullet and decode the text to binary, store it as a blob, and then re-encode it on the way out again?

Finally - load storage and performance are unlikely to cause problems, this is a pet project and will be low load.

Edit: In response to @howiecamp&#39;s question, I wrote up how I was URL encoding the image here: http://www.flowerchild.org.uk/archive/2010/06/13/base-64-encoding-an-image-to-pass-across-a-web.html

Which SQL data type to store Base64 encoded file?

The inbuilt Base64 library in Ruby is adding some &#39;\n&#39;s. I&#39;m unable to find out the reason. For this special example:

    irb(main):001:0&gt; require &#39;rubygems&#39;
    =&gt; true
    irb(main):002:0&gt; require &#39;base64&#39;
    =&gt; true
    irb(main):003:0&gt; str =  &quot;1110--ad6ca0b06e1fbeb7e6518a0418a73a6e04a67054&quot;
    =&gt; &quot;1110--ad6ca0b06e1fbeb7e6518a0418a73a6e04a67054&quot;
    irb(main):004:0&gt; Base64.encode64(str)
    =&gt; &quot;MTExMC0tYWQ2Y2EwYjA2ZTFmYmViN2U2NTE4YTA0MThhNzNhNmUwNGE2NzA1\nNA==\n&quot;

The \n&#39;s are at the last and 6th position from end. The decoder (Base64.decode64) returns back the old string perfectly. Strange thing is, these \n&#39;s don&#39;t add any value to the encoded string. When I remove the newlines from the output string, the decoder decodes it again perfectly.

    irb(main):005:0&gt; Base64.decode64(Base64.encode64(str).gsub(&quot;\n&quot;, &#39;&#39;)) == str
    =&gt; true

More of this, I used an another JS library to produce the base64 encoded output of the same input string, the output comes without the \n&#39;s.

Is this a bug or anything else? Has anybody faced this issue before?

FYI,

    $ ruby -v
    ruby 1.8.7 (2008-08-11 patchlevel 72) [i486-linux]



Strange \n in base64 encoded string in Ruby

Are there any methods in JavaScript that could be used to encode and decode a string using base64 encoding?

Base64 encoding and decoding in client-side Javascript

As the title says, I am getting: 

&gt; Invalid length for a Base-64 char
&gt; array.

I have read about this problem on here and it seems that the 
suggestion is to store ViewState in SQL if it is large. I am 
using a wizard with a good deal of data collection so chances
are my ViewState is large. But, before I turn to the &quot;store-in-DB&quot;
solution, maybe somebody can take a look and tell me if I have 
other options?

I construct the email for delivery using the below method:

    public void SendEmailAddressVerificationEmail(string userName, string to)
    {
        string msg = &quot;Please click on the link below or paste it into a browser to verify your email account.&lt;BR&gt;&lt;BR&gt;&quot; +
                        &quot;&lt;a href=\&quot;&quot; + _configuration.RootURL + &quot;Accounts/VerifyEmail.aspx?a=&quot; +
                        userName.Encrypt(&quot;verify&quot;) + &quot;\&quot;&gt;&quot; +
                        _configuration.RootURL + &quot;Accounts/VerifyEmail.aspx?a=&quot; +
                        userName.Encrypt(&quot;verify&quot;) + &quot;&lt;/a&gt;&quot;;

        SendEmail(to, &quot;&quot;, &quot;&quot;, &quot;Account created! Email verification required.&quot;, msg);
    }

The Encrypt method looks like this: 

    public static string Encrypt(string clearText, string Password)
    {
     
        byte[] clearBytes = System.Text.Encoding.Unicode.GetBytes(clearText);

        PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });

     
        byte[] encryptedData = Encrypt(clearBytes, pdb.GetBytes(32), pdb.GetBytes(16));

        return Convert.ToBase64String(encryptedData);
    }

Here is what the HTML looks like in hotmail:

&gt; Please click on the link below or
&gt; paste it into a browser to verify your
&gt; email account.
&gt; 
&gt; http://localhost:1563/Accounts/VerifyEmail.aspx?a=YOHY57xYRENEOu3H+FGq1Rf09AZAI56EPjfwuK8XWKg=

On the receiving end, the VerifyEmail.aspx.cs page has the line:

     string username = Cryptography.Decrypt(_webContext.UserNameToVerify, &quot;verify&quot;);

Here is the getter for UserNameToVerify:

    public string UserNameToVerify
    {
        get
        {
            return GetQueryStringValue(&quot;a&quot;).ToString();
        }
    }

And here is the GetQueryStringValue method:

    private static string GetQueryStringValue(string key)
    {
        return HttpContext.Current.Request.QueryString.Get(key);
    }

And the decrypt method looks like:

    public static string Decrypt(string cipherText, string password)
    {

        **// THE ERROR IS THROWN HERE!!**
        byte[] cipherBytes = Convert.FromBase64String(cipherText);

Can this error be remedied with a code fix or must I store ViewState in the database?

Invalid length for a Base-64 char array

Someone explain to me what `InputStream` and `OutputStream` are?

I am confused about the use cases for both `InputStream` and `OutputStream`.

If you could also include a snippet of code to go along with your explanation, that would be great. Thanks!

What is InputStream &amp; Output Stream? Why and when do we use them?

I have a blob column in my database table, for which I have to use `byte[]` in my Java program as a mapping and to use this data I have to convert it to `InputStream` or `OutputStream`. But I don&#39;t know what happens internally when I do so. Can anyone briefly explain me what&#39;s happening when I do this conversion?

Byte[] to InputStream or OutputStream

I have the following structure in a Java Web Application:

    TheProject
      -- [Web Pages]
      -- -- [WEB-INF]
      -- -- -- abc.txt
      -- -- index.jsp
      -- [Source Packages]
      -- -- [wservices]
      -- -- -- WS.java

In `WS.java`, I am using the following code in a Web Method:

    InputStream fstream = this.getClass().getResourceAsStream(&quot;abc.txt&quot;);

But it is always returning a null.  I need to read from that file, and I read that if you put the files in `WEB-INF`, you can access them with `getResourceAsStream`, yet the method is always returning a `null`.

Any ideas of what I may be doing wrong?

Btw, the strange thing is that this was working, but after I performed a `Clean and Build` on the Project, it suddenly stopped working :/

getResourceAsStream() is always returning null

In J2ME, I&#39;ve do this like that: 
`getClass().getResourceAsStream(&quot;/raw_resources.dat&quot;);`

But in android, I always get null on this, why?

How to get access to raw resources that I put in res folder?

What does `InputStream.available()` do in *Java*? I read the documentation, but I still cannot make it out.

The doc says:
&gt; 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. The next caller might be the same thread or or another thread.
&gt;
&gt;The available method for class InputStream always returns 0.

What do they mean by *blocking*? Does it just mean a synchronized call?

And most of all, what is the purpose of the `available()` method?

Content Type	Original Author	Original Content on Stackoverflow
Question	rover12	View Question on Stackoverflow
Solution 1 - Java	Daniel Rikowski	View Answer on Stackoverflow
Solution 2 - Java	Stephen Denne	View Answer on Stackoverflow

Can we convert a byte array into an InputStream in Java?

Java Problem Overview

Java Solutions

Solution 1 - Java

Solution 2 - Java

Is there a way to specify an "empty" C# lambda expression?

How to randomly sort (scramble) an array in Ruby?

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