face recognition java

depending on the subclass object).2, access modifier public,private,protected, and do not write (default) when the difference?For: Modifier Current class Same package Sub-class Other Packages Public √ √ √ √ Protected √ √ √ X Default √ √ X X Private √ X X X Defaults to default when members of a class do not write access

type variables? Volatile has two main functions: 1. Avoid command rearrangement 2. Visibility guarantees. For example, the JVM or JIT will reorder the statements for better performance, but the volatile type variable will not be reordered with other statements even if there are no synchronized blocks. Volatile provides happens-before guarantees that a thread's modifications can be visible to other threads. In some cases, volatile can also provide atomicity, such as reading 64-bit data type

two ways of jumping?Answer: There are two kinds, namely:The former page does not turn to the page that the include refers to, but displays the result of the page, the main page or the original. It will return after execution, equivalent to a function call. and can take parameters. The latter completely turns to the new page and will not come back. Equivalent to the go to statement.servlet aspect1. Say a servlet's life cycle?A: The servlet has a good definition of lifetime, including loading and

Java face test-frame eight 71, talk about your understanding of struts. 1. Struts is a web-layer framework designed in the MVC pattern, which is actually a servlet, the servlet named Actionservlet, or a subclass of Actionservlet. We can hand over all requests that meet a feature in the Web.xml file to this servlet, which then refer to a configuration file to assign each request separately to the different

Common Java face question questions: What if the Main method is declared private?Answer: Can compile normally, but will prompt "Main method is not public" when run.Question: What is the difference between a reference and a pass in Java?Answer: A pass-through refers to an address rather than the value itself, and a pass value is a copy of the passed value.Question

and checked exception. The checked exception is the IO exception that we often encounter, and the SQL exception is the exception. For this exception, the JAVA compiler enforces that we must catch the exceptions that occur. So, in the face of such anomalies whether we like it or not, we can only write a lot of catch blocks to deal with possible exceptions.But another exception: Runtime exception, also known

used by an expression or scriptlet. The added declaration must be wrapped up with the start and end Tags.114. what is an expression?"the list is very long and can be released in the top, middle, and bottom"A JSP expression is a Web server that converts the value of a script language expression into a string object that is inserted into the data stream returned to the Client. The expression is defined between the two tags, 115. what does the implied object mean? What are the hidden objects?JSP i

family God to our new beauty, as I used to be in everyone's time, every weekend to clean my station. Not to come, standing next to a goddess Harvester, I have some pressure.When a person stands in front of himself, in fact, his heart is very clear. Who is suitable, who is fond of. And the person who is right depends on the plan of his life. Planning to choose the right one to be happy, the person born for the talent will choose to like. If the next life is still the repetition of this life, eve

, write a generic program to implement the LRU cache?Can I use generics in 145,array?146, how do I write a generic method that can accept generic parameters and return generic types?What is the difference between a 147,c++ template and a Java generic?Win in the interview Javaweb chapter (15)What are some of the 148,ajax and weaknesses?What is the difference between a 149,ajax application and a traditional Web application?What is the implementation pro

, write a generic program to implement the LRU cache?Can I use generics in 145,array?146, how do I write a generic method that can accept generic parameters and return generic types?What is the difference between a 147,c++ template and a Java generic?Win in the interview Javaweb chapter (15)What are some of the 148,ajax and weaknesses?What is the difference between a 149,ajax application and a traditional Web application?What is the implementation pro

Java programmer face question day011.What is the difference between JDK and JRE ? What are their roles? Jdkis aJavadeveloped toolkit that mainly contains a variety of class libraries and tools such asJavac/javaw/java, but it also includes an additionalJRE,two different virtual machines are available,JDKof thebinthe directory hasClientand theServertwo files under

like Threadpoolexecutor and Scheduledthreadpoolexecutor have these methods.16. What is Readwritelock in Java?Generally speaking, read-write locks are the result of lock separation techniques used to improve concurrent program performance. Readwritelock in Java is a new interface in Java 5, a readwritelock maintains a pair of associated locks, one for read-only o

the progress is updated, the progress bar is changed accordingly. If the progress is tracked by multiple threads, call the Invokeandwait () method to request the event dispatch thread to update the component accordingly. The Invokelater () method is called to update the component asynchronously.138, what is the busy loop in multi-threading?A busy loop is when a programmer uses a loop to wait for a thread, unlike the traditional method wait (), sleep () or yield (), which discards CPU control, a

) * * @author Abe properties: face picture a deck of cards */public class mahjongs {//private static image[] images = new Image[36];p rivate mahjong[] mah = new Mahjong[108];p rivate int sheet = 0;//static {//static loader//for (int i = 0; i Mah[sheet++]: null; This is still a little vague to sheet after the output of the + +? }public mahjong[] getAll () {return mah;}}3. PrintingPackage com.lovo;/** * Mahjong * @author Abe * */public class Testmah {pu

(such as Tomcat), Java beans should have a parameterless constructor, and in addition, Java beans typically implement the serializable interface to implement Bean persistence. Java beans are actually equivalent to the local in-process COM component in the Microsoft COM model, which cannot be accessed across processes. Enterprise

declaration in Java and is used to declare a variable that is subsequently used by an expression or scriptlet. The added declaration must be wrapped up with the start and end tags.114. What is an expression?A JSP expression is a Web server that converts the value of a script language expression into a String object that is inserted into the data stream returned to the client. The expression is defined between the two tags, 115. What does the implied

(Numberformat.getinstance (locale.germany). Format (4032.3f)); // 4.032,3Formatting currencies using the default localeSystem.out.println (Numberformat.getcurrencyinstance (). Format (40324.31f)); // $40,324.31Format currency using locale settingsFormat currency using the Dutch locale:System.out.println (numberformat.getcurrencyinstance ( "NL")). Format (40324.31f)); // ? 40.324,31LicenseThis article, as well as any related source code and files, is based on the code Project Open License (Cpol)

1.GC What's that? Why is there a GC?GC is the meaning of garbage collection (Gabage Collection), memory processing is where programmers are prone to problems, forgetting or wrong memory recycling can cause program or system instability or even crashes, The GC functionality provided by Java can automatically monitor whether an object exceeds the scope to achieve the purpose of automatically reclaiming memory, and the

Controller: When the user clicks the Submit button in the Web page, the controller accepts the request and invokes the appropriate model to process the request. The corresponding view is then called according to the result of the processing to display the results of the processing. MVC process: First the controller accepts the user's request, invokes the corresponding model for business processing, and returns the data to the controller. The controller invokes the corresponding view to

post-processing on direct calls from clients, and to handle requests that are dispatched between WEB components behind a firewall. Finally, you can link the filters to provide the necessary functionality.Modular: By encapsulating application processing logic into a single class file, the filter defines a modular unit that can be easily added to or removed from the request/response chain.Portable: Like many other aspects of the Java platform, Servlet