## JodaTime

To convert JodaTime&#39;s [`org.joda.time.LocalDate`][1] to [`java.util.Date`][2], do

    Date date = localDate.toDateTimeAtStartOfDay().toDate();

To convert JodaTime&#39;s [`org.joda.time.LocalDateTime`][3] to [`java.util.Date`][2], do

    Date date = localDateTime.toDate();

---

## JavaTime

To convert Java8&#39;s [`java.time.LocalDate`][4] to [`java.util.Date`][5], do

    Date date = Date.from(localDate.atStartOfDay().atZone(ZoneId.systemDefault()).toInstant());

To convert Java8&#39;s [`java.time.LocalDateTime`][6] to [`java.util.Date`][5], do

    Date date = Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant());

You might be tempted to shorten it with `LocalDateTime#toInstant(ZoneOffset)`, but there isn&#39;t a direct API to obtain the system default zone offset.

To convert Java8&#39;s [`java.time.ZonedDateTime`][7] to [`java.util.Date`][5], do

    Date date = Date.from(zonedDateTime.toInstant());


  [1]: http://joda-time.sourceforge.net/apidocs/org/joda/time/LocalDate.html#toDateTimeAtStartOfDay()
  [2]: http://docs.oracle.com/javase/7/docs/api/java/util/Date.html
  [3]: http://joda-time.sourceforge.net/apidocs/org/joda/time/LocalDateTime.html#toDate()
  [4]: https://docs.oracle.com/javase/8/docs/api/java/time/LocalDate.html
  [5]: http://docs.oracle.com/javase/8/docs/api/java/util/Date.html#from-java.time.Instant-
  [6]: https://docs.oracle.com/javase/8/docs/api/java/time/LocalDateTime.html
  [7]: https://docs.oracle.com/javase/8/docs/api/java/time/ZonedDateTime.html

Since 2.0 version LocalDate has a [toDate()][1] method

    Date date = localDate.toDate();

If using version 1.5 - 2.0 use:

    Date date = localDate.toDateTimeAtStartOfDay().toDate();

On older versions you are left with:

    Date date = localDate.toDateMidnight().toDate();

[1]: http://joda-time.sourceforge.net/api-release/org/joda/time/LocalDate.html#toDate%28%29

You will need a timezone.

    LocalDate date = ...
    
    Date utilDate = date.toDateTimeAtStartOfDay( timeZone ).toDate( );



Maybe this?

    localDate.toDateTimeAtCurrentTime().toDate();


Try this.

new Date(localDate.toEpochDay())

I was asked this question in interview: &quot;How to detect the loop in linked list?&quot;, I solved this but immediately the interviewer asked me how do I remove the loop in a linked list.  I fumbled.

So any pointers on how to solve this, may be pseudo code, or method definition?

I&#39;m comfortable with Java so I have tagged this question under java.

For Instance this linked list has a loop

     0---&gt;1----&gt;2----&gt;3----&gt;4----&gt;5----&gt;6
                      ▲                 |
                      |                 ▼
                     11&lt;—-22&lt;—-12&lt;—-9&lt;—-8



Interview: Remove Loop in linked list - Java

I have a variable which is storing as decimal:

    decimal firststYrComp = Int16.Parse(tb1stYr.Text.ToString());

Now I have this to get typecasted into Double? How do I do that? Thanks!

Converting Decimal to Double in C#?

What is the simplest way to convert a JodaTime [`LocalDate`][1] to [`java.util.Date`][2] object?


  [1]: http://www.joda.org/joda-time/apidocs/org/joda/time/LocalDate.html
  [2]: http://download.oracle.com/javase/6/docs/api/java/util/Date.html

How to convert Joda LocalDate to java.util.Date?

<p>What is the simplest way to convert a JodaTime <a href="http://www.joda.org/joda-time/apidocs/org/joda/time/LocalDate.html" target="_blank" rel="noopener noreferrer"><code>LocalDate</code></a> to <a href="http://download.oracle.com/javase/6/docs/api/java/util/Date.html" target="_blank" rel="noopener noreferrer"><code>java.util.Date</code></a> object?</p>


It looks like `arraylist` is not doing its job for presizing:

    // presizing 
 
    ArrayList&lt;Integer&gt; list = new ArrayList&lt;Integer&gt;(60);

Afterwards when I try to access it:
  
    list.get(5) 

Instead of returning 0 it throws *IndexOutOfBoundsException: Index 5 out of bounds for length 0*.

Is there a way to initialize all elements to 0 of an exact size like what C++ does?
 



How can I initialize an ArrayList with all zeroes in Java?

let say I have this code

    Map&lt;String, String&gt; list = new HashMap&lt;String, String&gt;();
    list.put(&quot;number1&quot;, &quot;one&quot;);
    list.put(&quot;number2&quot;, &quot;two&quot;);


how can I make some &quot;alias&quot; the type

    Map&lt;String, String&gt;

to something that easier to be rewritten like

    // may be something like this
    theNewType = HashMap&lt;String, String&gt;;

    theNewType list = new theNewType();
    list.put(&quot;number1&quot;, &quot;one&quot;);
    list.put(&quot;number2&quot;, &quot;two&quot;);

basically my question is, how to create &quot;alias&quot; to some &quot;type&quot;, so i can make it easier to write and easier when need to change the whole program code.

Thanks, and sorry if this is silly question. I&#39;m kinda new in Java.



How do I create some variable type alias in Java

I&#39;m figuring out a mechanism to call an exe from Java and passing in specific parameters. How can I do?

    Process process = new ProcessBuilder(&quot;C:\\PathToExe\\MyExe.exe&quot;).start();
    InputStream is = process.getInputStream();
    InputStreamReader isr = new InputStreamReader(is);
    BufferedReader br = new BufferedReader(isr);
    String line;
    
    System.out.printf(&quot;Output of running %s is:&quot;, Arrays.toString(args));
    
    while ((line = br.readLine()) != null) {
      System.out.println(line);
    }

The previous code works. **But I&#39;m not able to pass parameters in**. MyExe.exe accepts parameters. An other problem is when PathToExe has blank spaces. ProcessBuilder seems not working. For example:

    C:\\User\\My applications\\MyExe.exe

Thank you.

Call an executable and pass parameters

Is there a way to capture a list of specific type using mockitos ArgumentCaptore. This doesn&#39;t work:

    ArgumentCaptor&lt;ArrayList&lt;SomeType&gt;&gt; argument = ArgumentCaptor.forClass(ArrayList.class);



How to capture a list of specific type with mockito

How can I convert a string to a Date object in JavaScript?

```js
var st = &quot;date in some format&quot;
var dt = new Date();

var dt_st = // st in Date format, same as dt.
```

Parsing a string to a date in JavaScript

I&#39;ve got GregorianCalendar instances and need to use SimpleDateFormat (or maybe something that can be used with calendar but that provides required #fromat() feature) to get needed output. Please, suggest work arounds as good as permanent solutions. 

How can I utilize SimpleDateFormat with Calendar?

I want to add months to a date in JavaScript.

For example: I am inserting date `06/01/2011` (format `mm/dd/yyyy`) and now I want to add 8 months to this date. I want the result to be `02/01/2012`.

So when adding months, the year may also increase.


How to add months to a date in JavaScript?

After 4 hours non-stop trying to resolve the problem I have decided to ask here if someone could help me.

The problem is that my Android client when tries to deserialize the data received from a server throw the &quot;Unparseable: 1302828677828&quot; exception.

I would like to know if it is possible to deserialize a millisecond-format date using Gson. 

&quot;Unparseable date: 1302828677828&quot; trying to deserialize with Gson a millisecond-format date received from server

I come from the C# world, so not too experienced with Java yet. I was just told by Eclipse that `Date` was deprecated:

    Person p = new Person();
    p.setDateOfBirth(new Date(1985, 1, 1));

Why? And what (especially in cases like above) should be used instead?

Java: Why is the Date constructor deprecated, and what do I use instead?

I have a date as a string in the following format `&quot;04/02/2011 20:27:05&quot;`. I am using Joda-Time library and would like to convert it to `DateTime` object. I did:

    DateTime dt = new DateTime(&quot;04/02/2011 20:27:05&quot;)

But I&#39;m getting the following error :

    Invalid format: &quot;04/02/2011 14:42:17&quot; is malformed at &quot;/02/2011 14:42:17&quot;

How to convert the above date to a `DateTime` object?

Converting a date string to a DateTime object using Joda Time library

How can i convert a string to a `LocalDate`?

I have seen examples like:

    LocalDate dt = new LocalDate(&quot;2005-11-12&quot;);

But my strings are like:

    2005-nov-12

String to LocalDate

are they happily married ?

I am using the latest version of hibernate (4) and version 1.3 of [joda-time hibernate support][1], which I also believe to be the current latest release. 

Everything seems to be working OK (date columns created as expected) when using annotations :

    @Column
    @Type(type=&quot;org.joda.time.contrib.hibernate.PersistentLocalDate&quot;)
    private LocalDate myDate; 

Are their any known problems with using these versions together ?

**Update**
Well turns out the columns get created but unable to populate with any data :

*Handler processing failed; nested exception is java.lang.AbstractMethodError: org.joda.time.contrib.hibernate.PersistentLocalDateTime.nullSafeSet*

**They are incompatible, and I should be using [usertype][2].** See answer below.


  [1]: http://www.joda.org/joda-time-hibernate/
  [2]: http://usertype.sourceforge.net/

hibernate 4 and joda-time

I am using JodaTime 1.6.2.

I have a `LocalDate` that I need to convert to either a (Joda) `LocalDateTime`, or a `java.sqlTimestamp` for ormapping.

The reason for this is I have figured out how to convert between a `LocalDateTime` and a `java.sql.Timestamp`:

    LocalDateTime ldt = new LocalDateTime();
    DateTimeFormatter dtf = DateTimeFormatter.forPattern(&quot;yyyy-MM-dd HH:mm:ss&quot;);
    Timestamp ts = Timestamp.valueOf(ldt.toString(dtf));

So, if I can just convert between `LocalDate` and `LocalDateTime`, then I can make the continued conversion to `java.sql.Timestamp`. Thanks for any nudges in the right direction!

Convert LocalDate to LocalDateTime or java.sql.Timestamp

I am currently creating UTC DateTime objects using the current idiom

    DateTime now = new DateTime(DateTimeZone.UTC);

Is there any way to default so I can create UTC-based DateTime objects using the default constructor so it is more implicit?

    DateTime now = new DateTime();

Content Type	Original Author	Original Content on Stackoverflow
Question	Eric Wilson	View Question on Stackoverflow
Solution 1 - Java	BalusC	View Answer on Stackoverflow
Solution 2 - Java	maraswrona	View Answer on Stackoverflow
Solution 3 - Java	Alexander Pogrebnyak	View Answer on Stackoverflow
Solution 4 - Java	Sean Patrick Floyd	View Answer on Stackoverflow
Solution 5 - Java	Alex Sales	View Answer on Stackoverflow

How to convert Joda LocalDate to java.util.Date?

Java Problem Overview

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JodaTime

JavaTime

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Converting Decimal to Double in C#?

Interview: Remove Loop in linked list - Java

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