Java

The IndexOf method returns an integer value that indicates the starting position of the substring in the string object. If no substring is found, 1 is returned.If the startindex is negative, then startindex is treated as zero. If it is larger than

1. Bubbling algorithm2. Quick Sort3. Merge sort4. Select sort5. Heap SequencingSorting algorithmsImportance is self-evident, many algorithm problems often choose a good sorting algorithm often problems can be solved1. Bubble algorithmBubble sort

Template Method Pattern (Templatemethod), which defines the skeleton of an algorithm in an operation, and delays some steps into subclasses. The template method allows subclasses to redefine some specific steps of the algorithm without altering the

1. Using binary to find the subscript of an array element2. But only if the array is sorted.3. Example:public static void Main (String ars []) {int [] number=new int []{2,6,9,45,65,88};}Publci staic int GetIndex (int [] Arr,int key) {int

Implement regular expression matching with support for ‘.‘ and ‘*‘ . ‘.‘ Matches any single character. ' * ' Matches zero or more of the preceding element. The matching should cover the entire input string (not partial). The function prototype

First, what is it?Shallow copy : Copy the value of a member variable of a value type , copy only a reference to a member variable of a reference type, and not copy the referenced object deep copy: a copy of a value for a member variable of a

Topic:Evaluate the value of an arithmetic expression in Reverse Polish Notation.Valid operators is + , - , * , / . Each operand is an integer or another expression.Some Examples:["2", "1", "+", "3", "*")--((2 + 1) (3)-9 ["4", "", "5", "/", "+"], 4 +

I. Exceptions1.1 During the execution of the program, the effect of the program is running normally.1.2 Exception Syntaxtry{code block}catch (Exception type E) {}catch (Exception type E) {｝... ｛}finally{｝Note:try: A block of code that represents an

The following is transferred from http://ifeve.com/deadlock/:A deadlock is two or more threads that block locks that are held by threads waiting for other deadlock states. Deadlocks typically occur when multiple threads are simultaneously requesting

The following is transferred from http://ifeve.com/deadlock-prevention/:In some cases deadlocks can be avoided. This article shows three techniques for avoiding deadlocks:Lock orderDeadlocks can easily occur when multiple threads require the same

Collected a small part, forget the time to come and checkJava--hadoop part/**@param @param @param @param cacheipnettypefilepath* [file cachefile need to upload HDFs, file for k-v form, multiple v with; separate]* * note: This class is suitable for

Final: Meaning immutable,Common terms Modify variables, method entry, methods, and classes1. Modify the variable, indicating that the variable can only be assigned directly or at the time of construction, not accept the second assignment, that is,

Topic:Implement the following operations of a stack using queues. Push (x)-push element x onto stack. Pop ()--Removes the element on top of the stack. Top ()--Get the top element. Empty ()--Return whether the stack is empty.

Here static, which is decorated with the static keyword, includes classes, methods, blocks, fields.Non-static, which is not modified with static.Static has some features:1. Globally unique, any modification is a global impact2. Load only once, prior

The following is transferred from http://ifeve.com/creating-and-starting-java-threads/:The Java thread class is also an object class, and its instances are inherited from Java.lang.Thread or its subclasses. You can create a thread in Java in the

HASHMAP:*map Interface: Store data in a way that is a key-value pair. Disordered* Common Implementation classes:*--hashmap: The implementation of a hash table-based MAP interface.* Common methods of construction:*hashmap () constructs an empty

Java multithreading is a complex issue, especially when multithreaded access to shared resources at any given time requires more attention. Java 5 introduces classes such as the blockingqueue and executors classes that provide an easy-to-use API

1. Unzip the zip file/*** Unzip the input zip stream, java default decompression can only handle UTF-8 encoded file or directory name, otherwise it will be reported malformed exception *@paramis input stream *@paramOutputFolder target Folder

Yesterday borrowed a "Web Design Experiment Tutorial (Java language)", and then read the first chapter, a swing example, so for everyone to share!As for the coding and decoding of the data, I think it has been explained very clearly in the example,

Differences between java Integer. valueOf and Integer. parseInt and new Integer and precautions: parseint and valueof First, let's look at the following results under explain. 1.System.out.println(127==127); //true , int type