java inheritance interview questions

, and the two subtrees of the root node are also a heap.⑦ Graph (graph)The graph is composed of set E of the node's poor set V and the edge. In order to distinguish with the tree structure, nodes are often called vertices in the graph structure,Edges are ordered pairs of vertices, and if there is an edge between the two vertices, it means that the two vertices have neighboring relationships.⑧ Hash List (hash)If there is a record of the same keyword and K in the structure, it must be in the stora

Multithreading and concurrency issues are among the questions that interviewers prefer to ask in a Java technology interview. Here, the most important questions are listed from the interview point of view, but you should still have a solid grasp of the basics of

Java programmer interview questions (86-115) 86. In Struts 2, how does Action obtain the data that the user inputs from the page, and how does it transmit its own data to the view? A: There are three ways for Action to retrieve data from the page: 1) accept parameters through the Action attribute 2) obtain parameters through the domain model 3) ModelDriven )

wrapper type , which means that the wrapper type can be converted directly to the base data type , as shown in the following code:int m=100; Integer im=int N=im; The appeal code directly assigns m to the wrapper object IM, which is automatically boxed and then directly assigns the IM to the basic data type N, which is the automatic unpacking. Although the code on the surface is simple and convenient, however, in essence, the container still uses new to create the object, while unpacking is s

. Briefly describe the meaning of the viewThe meaning of a view lies in two ways:1) simplify complex queries. If you need to perform a complex query frequently, you can build a view based on this complex query, and then query this view.2) Restrict data access. A view is essentially a SELECT statement, so when you access the view, you can only access the columns that are involved in the corresponding SELECT statement, and the other columns in the Base table act as security and secrecy.11. What ar

configuration. While JavaScript is interpreted to perform without generating intermediate files, "read a sentence, execute a sentence", the execution can generally be done in three ways:1. The general browser comes with the JS interpreter, which can be used directly by the browser;2. Special interpreter software can be installed node. js, executing the. js file;3. Executed with the Web page, using the Third, the data typeJava is a strongly typed language, and when it comes to data, the declarat

take out 1 position: Product: 4 The consumer takes out from 0 position: Product: 2 producer put in 0 position: Product: 5 consumer removed from 0 Position: Product: 5 producer put in 0 position: Product: 6 consumer is removed from 0 position: Product: 6 producer put in 0 Location: Product: 7 producer puts 1 position: products £ º The producers are placed in the location of the product: 8 Position: Product Consumer removed from 1 position: Product: 9 consumer removed from 0 positions: Products:

) {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

adapter pattern? Ø database How are you usually optimized, what other tools are used to optimize no, how to use the Ø Now there is a lot of tables to correlate the query SQL, the child table data is very much, then you only from the SQL point of view of the SQL statement optimization, do not need to consider the index, predicate Ø you don't have a Java project, do you? Ø your major is to control the direction, why do the current direction O you have

APIThe Java Collection Framework API is a unified framework for representing and manipulating collections, which contains interfaces, implementation classes, and algorithms that help programmers complete some programming. In short, the API does the following things on the top: more labor-efficient programming, improved City program speed and code quality, non-associative APIs to improve interoperability, saving on learning to use new API costs, savin