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A byte is a 8-bit signed integer. It can store a minimum value of -27 (-128), and a maximum value of 27 - 1 (127) byte example = -36; byte myByte = 96; byte anotherByte = 7; byte addedBytes = (byte) (myByte + anotherByte); // 103 byte subtractedBytes = (byte) (myBytes - anotherByte); // 89 ...

A float is a single-precision 32-bit IEEE 754 floating point number. By default, decimals are interpreted as doubles. To create a float, simply append an f to the decimal literal. double doubleExample = 0.5; // without 'f' after digits = double float floatExample = 0.5f; // with 'f' aft...

A double is a double-precision 64-bit IEEE 754 floating point number. double example = -7162.37; double myDouble = 974.21; double anotherDouble = 658.7; double addedDoubles = myDouble + anotherDouble; // 315.51 double subtractedDoubles = myDouble - anotherDouble; // 1632.91 double scientif...

Use the orElseThrow() method of Optional to get the contained value or throw an exception, if it hasn't been set. This is similar to calling get(), except that it allows for arbitrary exception types. The method takes a supplier that must return the exception to be thrown. In the first example, the...

By default, WebView does not implement JavaScript alert dialogs, ie. alert() will do nothing. In order to make you need to firstly enable JavaScript (obviously..), and then set a WebChromeClient to handle requests for alert dialogs from the page: webView.setWebChromeClient(new WebChromeClient() { ...

Once we've gotten the Connection, we will mostly use it to create Statement objects. Statements represent a single SQL transaction; they are used to execute a query, and retrieve the results (if any). Let's look at some examples: public void useConnection() throws SQLException{ Connection ...

A char can store a single 16-bit Unicode character. A character literal is enclosed in single quotes char myChar = 'u'; char myChar2 = '5'; char myChar3 = 65; // myChar3 == 'A' It has a minimum value of \u0000 (0 in the decimal representation, also called the null character) and a maximum valu...

The shared remote interface: package remote; import java.rmi.Remote; import java.rmi.RemoteException; public interface RemoteServer extends Remote { int stringToInt(String string) throws RemoteException; } The server implementing the shared remote interface: package server; im...

The + symbol can mean three distinct operators in Java: If there is no operand before the +, then it is the unary Plus operator. If there are two operands, and they are both numeric. then it is the binary Addition operator. If there are two operands, and at least one of them is a String, then i...

The Java language provides 7 operators that perform arithmetic on integer and floating point values. There are two + operators: The binary addition operator adds one number to another one. (There is also a binary + operator that performs string concatenation. That is described in a separate e...

The == and != operators are binary operators that evaluate to true or false depending on whether the operands are equal. The == operator gives true if the operands are equal and false otherwise. The != operator gives false if the operands are equal and true otherwise. These operators can be used ...

While using the foreach loop (or "extended for loop") is simple, it's sometimes beneficial to use the iterator directly. For example, if you want to output a bunch of comma-separated values, but don't want the last item to have a comma: List<String> yourData = //... Iterator<Str...

WebHistory history = webView.getEngine().getHistory(); The history is basically a list of entries. Each entry represents a visited page and it provides access to relevant page info, such as URL, title, and the date the page was last visited. The list can be obtained by using the getEntries() met...

You can use Scanner to read all of the text in the input as a String, by using \Z (entire input) as the delimiter. For example, this can be used to read all text in a text file in one line: String content = new Scanner(new File("filename")).useDelimiter("\\Z").next(); System.o...

Optional<String> optionalWithValue = Optional.of("foo"); optionalWithValue.ifPresent(System.out::println);//Prints "foo". Optional<String> emptyOptional = Optional.empty(); emptyOptional.ifPresent(System.out::println);//Does nothing.

DOM stands for Document Object Model. It is an object-oriented representation of structured documents like XML and HTML. Setting the textContent property of an Element is one way to output text on a web page. For example, consider the following HTML tag: <p id="paragraph"></p&g...

Variables can be incremented or decremented by 1 using the ++ and -- operators, respectively. When the ++ and -- operators follow variables, they are called post-increment and post-decrement respectively. int a = 10; a++; // a now equals 11 a--; // a now equals 10 again When the ++ and -- ope...

The dict() constructor can be used to create dictionaries from keyword arguments, or from a single iterable of key-value pairs, or from a single dictionary and keyword arguments. dict(a=1, b=2, c=3) # {'a': 1, 'b': 2, 'c': 3} dict([('d', 4), ('e', 5), ('f', 6)]) # {'d': 4, 'e': ...

At the command line, first verify that you have Git installed: On all operating systems: git --version On UNIX-like operating systems: which git If nothing is returned, or the command is not recognized, you may have to install Git on your system by downloading and running the installer. See...

Consider a database with the following two tables. Employees table: IdFNameLNameDeptId1JamesSmith32JohnJohnson4 Departments table: IdName1Sales2Marketing3Finance4IT Simple select statement * is the wildcard character used to select all available columns in a table. When used as a substitute f...