udemy java 8 course

Soon Blue Bridge Cup match, I these algorithms still not, indeed a bit of panic, today morning to sleep late not to get up, then began to study the 8 queen question. This is also a typical backtracking and recursion problem. In fact, and horse tread board problem very similar, eight Queen question, is to judge the main diagonal, diagonal, horizontal and vertical row can not have queen. This is the focus of the problem. Let's take a look at the eight Q

mixed-paradigm programming language like Scala and other languages. It is not difficult to understand how to implement functional encodings in Java 8 through the use of lambda expressions, method references, and higher-order functions.The hard part is how to flexibly integrate this new programming paradigm with the existing imperative object-oriented paradigm. This requires you to think carefully about the

tool programming languages, tools, and methodologies. That's why we want to accumulate as much experience as possible and use as many languages and frameworks. Focus on the basics of programming, because the basics never change: Focus more on architecture than programming. If you think there is only one right way to do things, then it may be time to test the actual combat. Dogma can hinder your ability to learn new things, and try to adapt yourself to change slowly.　　If you are interested in

[Java 8] Using Lambda expressions for DesignUse Lambda expressions for Design In the previous articles, we have seen how Lambda expressions make code more compact and concise. This article mainly introduces how Lambda expressions change program design and how to make programs more lightweight and concise. How to make the use of interfaces smoother and more intuitive.Use Lambda expressions to implement polic

wastes a lot of testing work, because most of the time is always doing unnecessary testing. But Delayqueue can avoid this kind of unnecessary detection. This queue implementation is also discussed in more detail in the Scheduled Tasks section of the online pool.Below is a section on common Blockingqueue, which does not include a two-way queue, although concurrentlinkedqueue is not a blocking queue, but it is also used to compare it together.If you do not need to block queues, prioritize concurr

requirements in our work: > Filter out non-conforming elements in a set to get a new set> convert each element in the set, process the converted set> calculate an attribute of the entire set, such as the sum or average of the element values of the set. These tasks are filter, map, and reduce tasks. They share the following features:You need to run a short piece of the same code for each element in the set. The traditional code for implementing these tasks is boring. Fortunately,

Java Chinese garbled solution (8) ----- solve the URL Chinese garbled problem, javaurl We mainly send requests to the server in two forms: URL and form. Forms generally do not have garbled characters. garbled characters are mainly related to URLs. Through the introduction of the previous blogs, we know that the process of sending Request Encoding from URLs to servers is too messy. Different operating system

Java training notes (8) MYSQL: functions are explained first today. functions are mainly divided into: 1. Aggregate functions 2. String functions 3. Date functions 4. mathematical functions Aggregate functions: A value is generated after a group of values are calculated. Common functions: function name function meaning Count () counts the maximum number of non-empty rows calculated by Max () and min,

/** * 5 Class (8 kinds) common internal sorting algorithm (for C, C + +, Java) * * Internal Sort Category: * 1) Insert sort (1. Direct insertion Sort, 2 hill sort) * 2 Exchange sort (1. Bubble sort, 2 quick sort) * 3) Select sort (1. Direct selection sort, 2. Heap sort) * 4) Merge sort * 5 allocation sort (cardinality sort) * * Author Wei Sama */ (1) Average time performance: the best way to quickly sort,

releasing the read lock. Lock get Interrupt Both the read lock and the write lock support the acquisition lock during the outage. This is consistent with the exclusive lock. Condition variable The write lock provides support for the conditional variable (Condition), which is consistent with the exclusive lock, but the read lock does not allow the conditional variable to get an UnsupportedOperationException exception. Re-entry number Th

Java design mode (8)-proxy Mode Proxy Mode1. in life:Proxy is a real life in which one person or organization represents others to do one thing. In some cases, a client does not want or cannot directly reference an object, and the proxy object can play a mediation role between the client and the target object.2. Official:The proxy mode is the structure mode of the object. The proxy mode provides a proxy obj

ObjectiveUsing PPA to install JDK in Ubuntu Server compared to the Oracle official website download package configuration environment Variables the benefit is that the installation is quick and easy, and can be apt-get updated.StepsAdd the PPA source of Java 8, may prompt add-apt-repository not installed, so need to install python-software-properties and Software-properties-common, add PPA source need to pr

how the above list interface Add method in JDK8 is resolved defaultvoidsort(Comparator Flip through the list interface's source code, which adds a default method of the defaults void sort (comparator List Comparator.naturalorder () is an implementation of a natural sort, where you can customize the sorting scheme. You often see the reason that you can directly forEach using the JAVA8 operation set is also a new de

Java training notes (8)-MYSQL Today, we will first explain the functions, which are mainly divided: 1. Aggregate functions 2. String Functions 3. Date Functions 4. mathematical functions Aggregate Function: A value is generated after a group of values are calculated. Common functions include: Function Name Function meaning Count () Count non-empty rows Max (), min () Ma

installation package creation tool, and finally press the entire program from 40 m to 8 M. Let's take a look at the entire operation process, and we will not write any tedious information about JRE slimming, sun's JRE slimming program is also underway. I believe that there will soon be a smaller slim version of JRE, and there is no need to bother myself.The following is a complete Java program named myload

(i), the concept of internal classes1, the internal class is a compile-time concept, once compiled successfully, it is with the peripheral class belongs to two completely different classes (of course they are still connected).2. For a perimeter class named Outerclass and an inner class named Innerclass, after a successful compilation,There will be two class files: Outerclass.class and Outerclass$innerclass.class.3, the use of internal classes The grea

other 12 Date date = Date.from(Instant.now());Instant instant = date.toInstant(); Date conversion to LocalDateTime 12 LocalDateTime localDateTime = LocalDateTime.from(newDate());System.out.println(localDateTime); LocalDateTime Turn Date 12 Date date =Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant()); Localdate Turn Date 12 Date date =Date.from(LocalDate.now().at

-point number;The default type of floating-point number is double type;A double type cannot also represent an exact value, such as a currency;The default value is 0.0d;Example: Double D1 = 123.4. BooleanThe Boolean data type represents one bit of information;Only two values: true and false;This type is only used as a sign to record the true/false situation;The default value is false;Example: Boolean one = True. CharThe char type is a single 16-bit Unicode character;Unicode is a fully interna

Java 8 new LocalDate and LocalTime interface, why do you have a new set of processing date and time API? Because the old java.util.Date really is too difficult to use.java.util.DateMonth from 0 start, January yes 0 , December Yes 11 , pervert bar! The java.time.LocalDate month and the week are changed enum , it is impossible to use the wrong again.java.util.DateAnd SimpleDateFormatter are not thread-safe, a

two numbers. 5) The parameter types in all LAMBDA expressions so far are inferred by the compiler. Of course it is.However, it is sometimes better to explicitly declare the parameter type, and you need to enclose the argument in parentheses, with multiple argumentsThe same is true of the situation.6) method Reference: A handy way to invoke parameters in a lambda expression.Such as:Artist , Artist.getname ()// can be written artist::