java concurrency interview questions

owns the lock gets the lock again, then the fetch counter increases by 1, and then the lock needs to be freed two times to get a true release. This mimics the semantics of synchronized; If a thread enters a synchronized block that is protected by a monitor that the thread already owns, it allows the thread to continue and does not release the lock when the thread exits the second (or subsequent) synchronized block. The lock is released only when the thread exits the first synchronized block tha

Interview Questions for Java engineers [social recruitment], java engineers Http://blog.csdn.net/jackfrued/article/details/44921941 1. What are the features of object orientation?2. What are the differences between access modifiers public, private, and protected?3. Is String the most basic data type?4. Is float f = 3.4

Java Collections Interview QuestionsIn Java, collection interview questions is mostly asked by the interviewers. Here are the list of mostly asked collections interview questions with a

Java Multithreading interview QuestionsMultithreading and synchronization are considered as the typical chapter in Java programming. In game development company, Mulithreading related interview questions is asked mostly. A List of frequently asked

Java Multithreaded interview questions 1. What is the difference between processes and threads? A process is a stand-alone (self contained) operating environment that can be viewed as a program or an application. A thread is a task that is performed in a process. The Java Runtime environment is a single process that

) {MapNewHashmap(); Premiumphone.put ("Apple", "IPhone"); Premiumphone.put ("HTC", "HTC One"); Premiumphone.put ("Samsung", "S5"); Iterator Iterator=Premiumphone.keyset (). iterator (); while(Iterator.hasnext ()) {System.out.println (Premiumphone.get (Iterator.next ())); Premiumphone.put ("Sony", "Xperia Z"); } } }"Main" java.util.ConcurrentModificationException at java.util.hashmap$hashiterator.nextentry (Unknown SOURCE) at Java.util.hashmap$keyiterator.next (Unknow

rewrite the aof file, the performance impact of this persistence is minimal, but the aof file will continue to grow, aof file over the General Assembly to affect the recovery speed of master restart. Master should not do any persistent work, including memory snapshots and aof log files, in particular, do not enable memory snapshots to persist, if the data is more critical, a slave open aof backup data, the policy is synchronized once per second. Master calls bgrewriteaof rewrite aof file, a

115 Java Interview Questions and answers-ultimate list (I), 115 java Object-Oriented Programming (OOP) Java is a computer programming language that supports concurrency, class-based, and object-oriented. The advantages of object

., GC can avoid memory leaks and stack overflow, effectively improve the efficiency of memory utilization, It also frees programmers from tedious memory management.The string S=new string ("xyz"); How many stringobject are created?2, 1 in the text pool, 1 in the heap, first create 1 "XYZ" objects in the text pool, and then copy an "XYZ" object in the heap and assign it to the reference S.Ninth, Math.Round (11.5) How much? Math.Round (-11.5) how much?Math.Round (x) equals (int) Math.floor (x+o.5f

The Java Collection framework is the foundation of the Java programming language and is an important knowledge point in the Java interview. Here, I've listed some important questions and answers about the Java collection.In additi

The Java Collection framework is the foundation of the Java programming language and is an important knowledge point in the Java interview. Here, I've listed some important questions and answers about the Java collection.In additi

. After creating an array or an object in the heap, you can also define a special variable in the stack that is equal to the first address of the array or object in the heap memory, and this variable in the stack becomes the reference variable of the array or object. The reference variable in the stack can then be used in the program to access an array or an object in the heap, which is equivalent to a name that is an array or an object.2 0. Can i cast int to a variable of type byte?What happens

Java Collection related interview questions and answers Interview questions1.JavaWhat is a collection 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 collect

Interview Questions and answers for 40 Java sets and 40 Java Sets Provided by Beijing shangxuetang 1. JavaWhat is a collection framework? What are the advantages of a collection framework? Each programming language has a set. The original Java version contains several collec

First, let's talk about the differences among final, finally, and finalize. Second, can Anonymous Inner Class (Anonymous internal Class) be extends (inherited) other classes, or implements (implemented) interface (interface )? Third, the difference between Static Nested Class and Inner Class is that the more you say, the better (the more general the interview questions are ). Fourth, the difference between

picture suffix 2, how to suffix is tampered with, then each file has a magic digital file upload-magic number5, the principle and implementation of Message Queuing Answer: 1, Message Queuing Principle 2, comprehensible message queue ActiveMQVi. Database Aspects1. The MySQL query field area is not case-sensitive?Answer: Do not differentiate, even if the value is not differentiated (I asked at the time, the area of the application of the size of the meaning of what, the interviewer did not say)2,

Let's talk about some questions about the java programmer interview. This blog post is intended for recent graduates and java programmers who have been working for about two or three years. Why do I need to change jobs? This is a broad question. Everyone has an answer. For example: The company is not well-treated, The

separately, which belongs to the salvage function operation.Interview question: Please explain the difference between ArrayList and Vector.· These two classes are subclasses of the List interface;· The Vector class is provided at JDK 1.0, and the method of operation provided is synchronous, so it is thread-safeThe Operation class;· The ArrayList class is provided at JDK 1.2, and the method provided is asynchronous, so it belongs to the non-linearProcess-safe Operation classes.If later in develo

dispatch and dispatch, and a smaller unit that can run independently than a process. Thread's StrokeThe sub-scale is less than the process, which makes the multi-threaded procedure highly concurrency, and the process typically has independent memory units at execution time, while the threads can share memory. Programming with multithreading often leads to better performance and user experience,But multithreaded programs are unfriendly to other progra

Java Exception Common interview question one, Java exception understandingExceptions are mainly handling errors that cannot be caught at compile time. The problem can continue to execute smoothly, without causing the program to terminate, to ensure the robustness of the program.Processing: When an abnormal state is generated, if the current context does not have