face recognition using java

synchronous.HashMap classHashMap and Hashtable are similar, except that HashMap is non-synchronous and allows NULL, which is null value and null key. , but when HashMap is treated as collection (the values () method returns collection), its iterator operation time overhead is proportional to the capacity of HashMap. Therefore, if the performance of the iterative operation is quite important, do not set the initialization capacity of the hashmap too high or load factor too low.Weakhashmap classW

objects whose string type property s all point to the same object. The above conclusion is also based on the fact that, for string constants, if the content is the same, Java considers them to represent the same string object. Calling the constructor with the keyword new always creates a new object, regardless of whether the content is the same. As for why the string class is designed as an immutable class, it is the purpose of its decision. In fact,

JS Object-Oriented Programming learning notes Javascrpt does not contain Class (class)So some people call the classPrototype object. The two concepts play the same role in programming. We only use JavaScript as a functional language, and only use it for some simple front-end data input verification and some simple page dynamic effects. In many excellent Ajax frameworks, such as extjs and jquery, the face Object Features of JavaScript are widely used.

implementation), they all complete the map interface, the main difference is that the HASHMAP allows null (NULL) key value (key), because of non-thread security, in the case of only one thread access, More efficient than Hashtable.HashMap allows NULL to be used as a entry key or value, and Hashtable is not allowed.HashMap hashtable contains method removed, changed to Containsvalue and ContainsKey. Because the contains method is easy to cause misunderstanding.Hashtable inherits from the dictiona

daemon thread? What's the use?22, how to interrupt a thread? How to ensure the interruption of business is not affected?23. What is the yield () method used for?24. What is the difference between a re-entry lock and a synchronized lock?25. What kinds of usages do synchronized have?26. What does the Fork/join framework do?27, how to pass parameters to the thread?28. Talk about thread-safe and unsafe collections.29, what is the CAS algorithm? What are the applications in multi-threading.30. What

implemented Technical depth Have you seen the JDK source code, see the class implementation principle is what. HTTP protocol TCP protocol Consistent hash algorithm How the JVM loads bytecode files How the ClassLoader unloads bytecode The difference between IO and NIO, NIO benefits Java thread Pool Implementation principle, KeepAliveTime parameters such as the role. HTTP connection Pooling Implementation p

number is exactly equal to the sum of its factors, this number is called the "end number". Write an application and a small application to find all the numbers within 1000.public class Wanshu {public static void Main (string[] args) {int sum=0,i,j;for (i=1;i{for (j=1,sum=0;j{if (i%j==0)Sum=sum+j;}if (sum==i){System.out.print ("End number:" +i+ "" + "its factor is:");for (int k=1;k{if (sum%k==0)System.out.print ("+k");}System.out.println ();}}}}9) Read several numbers from the keyboard, end with

student." Turn into "student." A am I "According to the example given in the topic, we should have a word exchange here, so it is no longer like the rotation of each character abovePackage Com.ray.datastructure.ch01.topic_1_1;public class Reversestring_3 {public static string reverse (string source, string regex, int start, int end) {string[] Strarray = Source.split (regex); while (start Test output:Student. A am IIn general terms, the above is better, because it can customize the exchange of w

the name of the inner class is superfluous, soThe anonymous inner class is used.3, how to implement anonymous internal class? The implementation of an anonymous inner class is very simple, such as having an interface Interface a{public void Method (); At this point you can write a statement like the following to get the implementation class of interface a a=new a () {public void method () {System.out.println ("hehe");}};And where {public void method () {System.out.println ("hehe");}}; is to

Title: Write a function, enter n, and find the nth of the Fibonacci Sequence.1 packagesolution;2 3 /**4 * Sword Point offer question 9: Fibonacci sequence5 * Title: Write a function, enter n, and find the nth of the Fibonacci Sequence. 6 * 0, n=17 * The Fibonacci sequence is defined as follows: f (n) = 1, n=28 * F (n-1) +f (n-2), n>29 * @authorGLTen * one */ a public classNo9fibonacci { - - public Static voidmain (string[] Args) { theSystem.out.println (the Value of the 4th Xiang Feip

single-threaded program can not produce OutOfMemoryError exception, using multithreading will also appear outofmemeoryerror, because the stack is thread-private, line multithreading also overflow method area3, JVM stack space allocation over the General Assembly caused by what problemshttp://blog.csdn.net/qq_30739519/article/details/510425844. How to detect dead loops and deadlocks in the JVMDeadlock: http://www.cnblogs.com/ilahsa/archive/2013/06/03/

-order traversal of the following two-fork trees are written:3. What's wrong with the following procedure?public class Something{public static void Main (string[] args) {SomeThing s=new SomeThing (); System.out.println ("The S.dosomething () is" +dosomething ());} Public String dosomething () {return ' do something ';}}4. Insert sort and bubble sort which is good, why?5. What are the output results of the following programs?public class Test{public static int y=8;public staitic void main (string

class of the system, such as string, etc. are inside, this package is the only one can be used without import packageJava.io: This is all the input and output related classes, such as file operation, etc.Java.net: This is a network-related class, such as Url,urlconnection.Java.util: This is the system auxiliary class, especially the collection class Collection,list,map and so on.java.sql: This is the database operation class, Connection, Statememt,resultset, etc.What are the characteristics of

the read operation because the object and write operation is not the same object, read between the need to lock, the synchronization between read and write only after writing through a simple "=" To point a reference to a new array object, which hardly takes time, so that the read operation is very safe, suitable for use in multi-threading, never concurrentmodificationexception, So copyonwritearraylist is suitable for scenarios where read operations are much larger than write operations, such a

occupied, it is locked, and the thread attempts to take ownership of the monitor while executing the monitorenter instruction, as follows: If the monitor has an entry number of 0, the thread enters monitor and then sets the entry number to 1, which is the owner of the Monitor. If the thread already occupies the monitor, just re-enter, then enter the monitor number plus 1. If another thread has already occupied monitor, the thread goes into a blocking state until the numbe

62. Talk about your understanding of MyBatis?MyBatis is an open source project for Apache Ibatis, which was migrated to Google code by the Apache Software Foundation in 2010 and renamed MyBatis. Migrated to GitHub in November 2013.MyBatis is an excellent persistence layer framework that encapsulates the process of using JDBC to manipulate databases, allowing developers to focus on the SQL itself without having to expend effort to process such as regis

. When the data increases, it may exceed the number of elements originally defined, and when the data is reduced, the memory is wasted; the array can be accessed directly from the subscript. The ② linked list is dynamically stored and allocated, which can adapt to the dynamic increase or decrease of data, and can easily insert and delete data items. (when inserting and deleting data items in an array, it is tedious to move other data items) The linked list must find the next element based on the

What is the 1.Java set frame? What are some of the advantages of a collection framework? There are collections in each programming language, and the original Java version contains several collection classes: vectors, Stack, Hashtable, and array. With the extensive use of the set, Java1.2 proposes a set framework encompassing all the set interfaces, implementations, and algorithms.

about the details of HashMap's more basic. The interviewer may ask the following questions:"Do you know how HashMap works?" "Do you know how the HashMap get () method works?" ”You may be able to answer, "I didn't look up the standard Java API, you can look at Java source code or open JDK." "I can use Google to find the answer." ”But some interviewers may be able to give the answer, "HashMap is based on the

Java face test-web 15 148,ajax have some and disadvantages. Advantages: 1, the biggest point is the page does not refresh, the user experience is very good. 2, the use of asynchronous way to communicate with the server, with more rapid response capabilities. 3, can put some of the previous server burden to the client, the use of idle client capacity to deal with, reduce the burden of server and bandwidth,