`subList` returns a *view* on an existing list. It&#39;s not an `ArrayList`. You can create a *copy* of it:

    sibling.keys = new ArrayList&lt;Integer&gt;(keys.subList(mid, this.num));

Or if you&#39;re happy with the view behaviour, try to change the type of `sibling.keys` to just be `List&lt;Integer&gt;` instead of `ArrayList&lt;Integer&gt;`, so that you don&#39;t need to make the copy:

    sibling.keys = keys.subList(mid, this.num);

It&#39;s important that you understand the difference though - are you going to mutate `sibling.keys` (e.g. adding values to it or changing existing elements)? Are you going to mutate `keys`? Do you want mutation of one list to affect the other?


You get the class cast exception because you are expecting an ArraList while the ArrayList.subList()does not return ArrayList.
**Change your sibling.keys from ArrayList to List**, and should work fine. This will avoid ClassCastException as well as you will not need to and any cast.



I need to find the last day of a month in the following format:

    &quot;2013-05-31 00:00:00:000&quot;

Anybody please help out.

SQL Query to find the last day of the month

I&#39;m using a an `ObservableCollection` with two `ICollectionView` for different filters.

One is for filtering messages by some type, and one is for counting checked messages.
As you can see message filter and message count works OK, but when I&#39;m un-checking the message disappear from the list (*the count is still working*).

BTW sorry for the long post, I wanted to include all relevant stuff.

**The XAML Code:**

    &lt;!-- Messages List --&gt;
    &lt;DockPanel Grid.Row=&quot;1&quot;
               Grid.Column=&quot;0&quot;
               Grid.ColumnSpan=&quot;3&quot;
               Height=&quot;500&quot;&gt;
      &lt;ListBox Name=&quot;listBoxZone&quot;
               ItemsSource=&quot;{Binding filteredMessageList}&quot;
               Background=&quot;Transparent&quot;
               BorderThickness=&quot;0&quot;&gt;
        &lt;ListBox.ItemTemplate&gt;
          &lt;DataTemplate&gt;
            &lt;CheckBox Name=&quot;CheckBoxZone&quot;
                      Content=&quot;{Binding text}&quot;
                      Tag=&quot;{Binding id}&quot;
                      Unchecked=&quot;CheckBoxZone_Unchecked&quot;
                      Foreground=&quot;WhiteSmoke&quot;
                      Margin=&quot;0,5,0,0&quot;
                      IsChecked=&quot;{Binding isChecked}&quot; /&gt;
          &lt;/DataTemplate&gt;
        &lt;/ListBox.ItemTemplate&gt;
      &lt;/ListBox&gt;
    &lt;/DockPanel&gt;
    &lt;Button Content=&quot;Test Add New&quot;
            Grid.Column=&quot;2&quot;
            Height=&quot;25&quot;
            HorizontalAlignment=&quot;Left&quot;
            Margin=&quot;34,2,0,0&quot;
            Click=&quot;button1_Click&quot; /&gt;
    &lt;Label Content=&quot;{Binding checkedMessageList.Count}&quot;
           Grid.Column=&quot;2&quot;
           Height=&quot;25&quot;
           Margin=&quot;147,2,373,0&quot;
           Width=&quot;20&quot;
           Foreground=&quot;white&quot; /&gt;

**Screenshot:**
![enter image description here][1]

**Code:**

    /* ViewModel Class */
    public class MainViewModel : INotifyPropertyChanged
    {

        // Constructor
        public MainViewModel()
        {
            #region filteredMessageList
            // connect the ObservableCollection to CollectionView
            _filteredMessageList = CollectionViewSource.GetDefaultView(messageList);
            // set filter 
            _filteredMessageList.Filter = delegate(object item)
            {
                MessageClass temp = item as MessageClass;

                if ( selectedFilter.Equals(AvailableFilters.All) )
                {
                    return true;
                }
                else
                {
                    return temp.filter.Equals(_selectedFilter);
                }
            };
            #endregion

            #region checkedMessageList
            // connect the ObservableCollection to CollectionView
            _checkedMessageList = CollectionViewSource.GetDefaultView(messageList);
            // set filter 
            _checkedMessageList.Filter = delegate(object item) { return (item as MessageClass).isChecked; };
            #endregion
        }

        // message List
        private ObservableCollection&lt;MessageClass&gt; _messageList =
                new ObservableCollection&lt;MessageClass&gt;();
        public ObservableCollection&lt;MessageClass&gt; messageList
        {
            get { return _messageList; }
            set { _messageList = value; }
        }

        // CollectionView (filtered messageList)
        private ICollectionView _filteredMessageList;
        public ICollectionView filteredMessageList
        {
            get { return _filteredMessageList; }
        }

        // CollectionView (filtered messageList)
        private ICollectionView _checkedMessageList;
        public ICollectionView checkedMessageList
        {
            get { return _checkedMessageList; }
        }

        // SelectedFilter property
        private AvailableFilters _selectedFilter = AvailableFilters.All; // Default is set to all
        public AvailableFilters selectedFilter
        {
            get { return _selectedFilter; }
            set
            {
                _selectedFilter = value;
                RaisePropertyChanged(&quot;selectedFilter&quot;);
                _filteredMessageList.Refresh(); // refresh list upon update
            }
        }

        // FilterList (Convert Enum To Collection)
        private List&lt;KeyValuePair&lt;string, AvailableFilters&gt;&gt; _AvailableFiltersList;
        public List&lt;KeyValuePair&lt;string, AvailableFilters&gt;&gt; AvailableFiltersList
        {
            get
            {
                /* Check if such list available, if not create for first use */
                if (_AvailableFiltersList == null)
                {
                    _AvailableFiltersList = new List&lt;KeyValuePair&lt;string, AvailableFilters&gt;&gt;();
                    foreach (AvailableFilters filter in Enum.GetValues(typeof(AvailableFilters)))
                    {
                        string Description;
                        FieldInfo fieldInfo = filter.GetType().GetField(filter.ToString());
                        DescriptionAttribute[] attributes =
                                    (DescriptionAttribute[])fieldInfo.GetCustomAttributes(typeof(DescriptionAttribute), false);

                        /* if not null get description */
                        if (attributes != null &amp;&amp; attributes.Length &gt; 0)
                        {
                            Description = attributes[0].Description;
                        }
                        else
                        {
                            Description = string.Empty;
                        }

                        /* add as new item to filterList */
                        KeyValuePair&lt;string, AvailableFilters&gt; TypeKeyValue =
                                    new KeyValuePair&lt;string, AvailableFilters&gt;(Description, filter);

                        _AvailableFiltersList.Add(TypeKeyValue);
                    }
                }
                return _AvailableFiltersList;
            }
        }

        #region Implement INotifyPropertyChanged
        public event PropertyChangedEventHandler PropertyChanged;
        public void RaisePropertyChanged(string propertyName)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
        }
        #endregion
    }


**Code For un-check function**
        
    private void CheckBoxZone_Unchecked(object sender, RoutedEventArgs e)
    {
        CheckBox chkZone = (CheckBox)sender;
        ucSystemMessageVM.checkedMessageList.Refresh();
    }

  [1]: http://i.stack.imgur.com/cVYM6.gif

WPF Multiple CollectionView with different filters on same collection

Im using an ArrayList and im trying to copy a part of it to another ArrayList therefore im using:

    sibling.keys = (ArrayList&lt;Integer&gt;) keys.subList(mid, this.num);

Where &quot;sibling.keys&quot; is the new ArrayList and &quot;keys or this.keys&quot; is the older ArrayList.
I used the casting because eclipse told me to do that but then it throws a `ClassCastException`:

&gt; java.util.ArrayList$SubList cannot be cast to java.util.ArrayList

Any advice?

Converting a subList of an ArrayList to an ArrayList

Im using an ArrayList and im trying to copy a part of it to another ArrayList therefore im using:
<pre><code class="hljs language-ini">sibling.keys = (ArrayList&#x3C;Integer>) keys.subList(mid, this.num);
</code></pre>
Where "sibling.keys" is the new ArrayList and "keys or this.keys" is the older ArrayList.
I used the casting because eclipse told me to do that but then it throws a <code>ClassCastException</code>:
> java.util.ArrayList$SubList cannot be cast to java.util.ArrayList
Any advice?

Is there any way to convert a File object to MultiPartFile? So that I can send that object to methods that accept the objects of `MultiPartFile` interface?


    File myFile = new File(&quot;/path/to/the/file.txt&quot;)
    
    MultiPartFile ....?

    def (MultiPartFile file) {
      def is = new BufferedInputStream(file.getInputStream())
      //do something interesting with the stream
    }

Converting File to MultiPartFile

I am using Spring MVC .I have to write a service that would take input from the request body, add the data to the pdf and returns the pdf file to the browser. The pdf document is generated using itextpdf.
How can I do this using Spring MVC. I have tried using this

    @RequestMapping(value=&quot;/getpdf&quot;, method=RequestMethod.POST)
    public Document getPDF(HttpServletRequest request , HttpServletResponse response, 
          @RequestBody String json) throws Exception {
        response.setContentType(&quot;application/pdf&quot;);
        response.setHeader(&quot;Content-Disposition&quot;, &quot;attachment:filename=report.pdf&quot;);
        OutputStream out = response.getOutputStream();
        Document doc = PdfUtil.showHelp(emp);
        return doc;
    }

showhelp function that generates the pdf. I am just putting some random data in the pdf for time being.

    public static Document showHelp(Employee emp) throws Exception {
        Document document = new Document();
       
        PdfWriter.getInstance(document, new FileOutputStream(&quot;C:/tmp/report.pdf&quot;));
        document.open();
        document.add(new Paragraph(&quot;table&quot;));
        document.add(new Paragraph(new Date().toString()));
        PdfPTable table=new PdfPTable(2);

        PdfPCell cell = new PdfPCell (new Paragraph (&quot;table&quot;));

        cell.setColspan (2);
        cell.setHorizontalAlignment (Element.ALIGN_CENTER);
        cell.setPadding (10.0f);
        cell.setBackgroundColor (new BaseColor (140, 221, 8));                                  

        table.addCell(cell);                                    
        ArrayList&lt;String[]&gt; row=new ArrayList&lt;String[]&gt;();
        String[] data=new String[2];
        data[0]=&quot;1&quot;;
        data[1]=&quot;2&quot;;
        String[] data1=new String[2];
        data1[0]=&quot;3&quot;;
        data1[1]=&quot;4&quot;;
        row.add(data);
        row.add(data1);
        
        for(int i=0;i&lt;row.size();i++) {
          String[] cols=row.get(i);
          for(int j=0;j&lt;cols.length;j++){
            table.addCell(cols[j]);
          }
        }
                  
        document.add(table);
        document.close();
        
        return document;   
    }

I am sure this is wrong. I want that pdf to be generated and save/open dialog box to be opened through the browser, so that it can be stored in the client&#39;s file system. Please help me out.

Return generated pdf using spring MVC

What is the relationship/difference between `sourceCompatibility` and `targetCompatibility`? What happens when they are set to different values?

According to [Gradle documentation](http://www.gradle.org/docs/current/userguide/java_plugin.html):

`sourceCompatibility` is &quot;Java version compatibility to use when compiling Java source.&quot;
`targetCompatibility` is &quot;Java version to generate classes for.&quot;

My understanding is that `targetCompatibility` will generate java bytecode that is compatible with a specific version of Java, is this a subset of the functionality of `sourceCompatibility`?



Gradle, &quot;sourceCompatibility&quot; vs &quot;targetCompatibility&quot;?

Suppose I have a `value`, I usually do this to &quot;clamp&quot; it to a range, here the range `[0..1]`. That is if it is below the range start, increase it to the range start, it above the range end, reduce it to the range end.

    clampedValue = Math.max(0, Math.min(1, value));

Is there any built in function for clamping to a range?

Does java have a clamp function?

I am writing a code which task is to retrieve a requested URL or full path. I&#39;ve written this code: 
     

    HttpServletRequest request;//obtained from other functions
    String uri = request.getRequestURI();
    if (request.getQueryString() != null)
        uri += &quot;?&quot; + request.getQueryString();
         
So, when I browse `http://google.com?q=abc` it is OK (correct).
But there is problem when I browse `https://google.com`. The value of `uri` is `http://google.com:443google.com:443`, So the program doesn&#39;t only when `HTTPS` is used.

And the output is same for `request.getRequestURL().toString()`. 

What is the solution?   


Get full URL and query string in Servlet for both HTTP and HTTPS requests

I&#39;m trying to read in from two files and store them in two separate arraylists. The files consist of words which are either alone on a line or multiple words separated by commas.
I read each file with the following code (not complete):

    ArrayList&lt;String&gt; temp = new ArrayList&lt;&gt;();

    FileInputStream fis;
    fis = new FileInputStream(fileName);

    Scanner scan = new Scanner(fis);

    while (scan.hasNextLine()) {
        Scanner input = new Scanner(scan.nextLine());
        input.useDelimiter(&quot;,&quot;);
        while (scan.hasNext()) {
            String md5 = scan.next();
            temp.add(md5);
        }
    }
    scan.close();    

    return temp;

I now need to read two files in and remove all words from the first file which also exist in the second file (there are some duplicate words in the files). I have tried with for-loops and other such stuff, but nothing has worked so any help would be greatly appreciated!

Bonus question: I also need to find out how many duplicates there are in the two files - I&#39;ve done this by adding both arraylists to a HashSet and then subtracting the size of the set from the combined size of the two arraylists - is this a good solution, or could it be done better?

Remove all objects in an arraylist that exist in another arraylist

How can I find an object, `Carnet`, in a `ArrayList&lt;Carnet&gt;` knowing its property `codeIsin`.

    List&lt;Carnet&gt; listCarnet = carnetEJB.findAll();

    public class Carnet {
    
        private String codeTitre;
        private String nomTitre;
        private String codeIsin;

        // Setters and getters
  
    }

How to find an object in an ArrayList by property

I&#39;ve seen several other questions similiar to this one but I haven&#39;t really been able to find anything that resolves my problem. 

My use case is this: user has a list of items initially (listA). They reorder the items and want to persist that order (listB), however, due to restrictions I&#39;m unable persist the order on the backend so I have to sort listA after I retrieve it.

So basically, I have 2 ArrayLists (listA and listB). One with the specific order the lists should be in (listB) and the other has the list of items (listA). I want to sort listA based on listB.


In Java how do you sort one list based on another?

I have a class named Fruit. I am creating a list of this class and adding each fruit in the list. I want to sort this list based on the order of fruit name.

    public class Fruit{
     
    	private String fruitName;
    	private String fruitDesc;
    	private int quantity;
     
    	public String getFruitName() {
    		return fruitName;
    	}
    	public void setFruitName(String fruitName) {
    		this.fruitName = fruitName;
    	}
    	public String getFruitDesc() {
    		return fruitDesc;
    	}
    	public void setFruitDesc(String fruitDesc) {
    		this.fruitDesc = fruitDesc;
    	}
    	public int getQuantity() {
    		return quantity;
    	}
    	public void setQuantity(int quantity) {
    		this.quantity = quantity;
    	}
    }

and I am creating its list using for loop

    List&lt;Fruit&gt;  fruits= new ArrayList&lt;Fruit&gt;();
    
    Fruit fruit;
    for(int i=0;i&lt;100;i++)
    {
       fruit = new fruit();
       fruit.setname(...);
       fruits.add(fruit);
    }

and I need to sort this arrayList using the fruit name of each object in the list

how??

How to sort an ArrayList in Java

I&#39;m trying to remove some elements from an `ArrayList` while iterating it like this:

    for (String str : myArrayList) {
        if (someCondition) {
            myArrayList.remove(str);
        }
    }

Of course, I get a `ConcurrentModificationException` when trying to remove items from the list at the same time when iterating `myArrayList`. Is there some simple solution to solve this problem?

Content Type	Original Author	Original Content on Stackoverflow
Question	yoavgray	View Question on Stackoverflow
Solution 1 - Java	Jon Skeet	View Answer on Stackoverflow
Solution 2 - Java	Ankur Shanbhag	View Answer on Stackoverflow

Converting a subList of an ArrayList to an ArrayList

Java Problem Overview

Java Solutions

Solution 1 - Java

Solution 2 - Java

WPF Multiple CollectionView with different filters on same collection

SQL Query to find the last day of the month

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