What is selector and channel in NIO?
A selector provides a mechanism for monitoring one or more NIO channels and recognizing when one or more become available for data transfer. This way, a single thread can be used for managing multiple channels, and thus multiple network connections.
What is Java NIO Selector?
The Java NIO Selector is a component which can examine one or more Java NIO Channel instances, and determine which channels are ready for e.g. reading or writing. This way a single thread can manage multiple channels, and thus multiple network connections.
Is Java selector thread safe?
Selector objects are thread-safe, but the key sets they contain are not. The key sets returned by the keys( ) and selectedKeys( ) methods are direct references to private Set objects inside the Selector object.
What is ServerSocketChannel?
A Java NIO ServerSocketChannel is a channel that can listen for incoming TCP connections, just like a ServerSocket in standard Java Networking. The ServerSocketChannel class is located in the java. nio. channels package.
How do you create a selector in Java?
A selector may be created by invoking the open method of this class, which will use the system’s default selector provider to create a new selector. A selector may also be created by invoking the openSelector method of a custom selector provider. A selector remains open until it is closed via its close method.
What is a selection key?
A selection key is created each time a channel is registered with a selector. A key remains valid until it is cancelled by invoking its cancel method, by closing its channel, or by closing its selector. The validity of a key may be tested by invoking its isValid method.
What is NIO API?
nio (NIO stands for non-blocking I/O) is a collection of Java programming language APIs that offer features for intensive I/O operations. It was introduced with the J2SE 1.4 release of Java by Sun Microsystems to complement an existing standard I/O. NIO was developed under the Java Community Process as JSR 51.
What is Socketchannel in Java?
Java NIO socket channel is a selectable type channel which means it can be multiplexed using selector, used for stream oriented data flow connecting sockets. Once channel is get connected,it remains connected until it is closed. The state of socket channel may be determined by invoking its isConnected method.
How do I select text without clicking and dragging?
Click the “Select” drop-down menu in the Editing group on the ribbon and choose “Select All.” All of the body text on the pages will be highlighted. You can now format it, cut, copy, align the text and more. The keyboard shortcut “Ctrl-A” will accomplish the same result.
How do you use the select key?
Hold down the “Ctrl” key and the “Shift” key. Press the right arrow key to select the word to the right, or press the left arrow key to select the word to the left. Select one character at a time by holding down the “Shift” key and and using either arrow key (right or left).