java interview questions on strings

Java Basic topics:1. After executing the following statements, the values of I and n are, int i=10;int n=i++%5;Results: i=11,n=02, for the following code which expression return value is True:bpublic class sample{Long length;Public Sample (Long L) {length=l;}public static void Main (String[]args){Sample S1,s2,s3;S1=new Sample (211);S2=new Sample (211);S3=S2;}}A S1==S2B S2.equals (S3)C s1.equals (S2)D S2!=S3Note: = = differs from equals:(1) = = is an o

, instead of going to the pool to findView the following API documentation in the specific method in theCalling a method in any string does not change the string itself unless the value is re-assigned.StringBuffer: A sequence of Unicode characters that can be changedAllows concurrent operations, which are thread-safeThe string class is inefficient in connection with strings because the properties of the object it produces cannot be modified, and only

"032-longest Valid parentheses (maximum effective bracket)""leetcode-Interview algorithm classic-java Implementation" "All topics Directory Index"Original QuestionGiven A string containing just the characters ‘(‘ ‘)‘ and, find the length of the longest valid (well-formed) parenthe SES substring."(()"for, the longest valid parentheses substring "()" are, which has length = 2.Another example ")()())" is, wher

the change in performance efficiency, so it is recommended that you consider using the StringBuffer class directly when you need to append strings. Reference answer:The String class is an immutable class, where the string value cannot be changed once it is initialized. StringBuffer is a mutable string class, string-like buffer that can modify the value of a string .3 The difference between StringBuffer and StringbiulderStringBuffer is a thread-safe s

configured Java language post-compilation sound field The most basic storage unit for a computer is: bytesComputer direct recognition of binary: binary What is the difference between a variable and a constant:The value of a variable during the operation is varied, can be assigned multiple times, and the constant is fixed. Categories of variable data types:Variables need to be defined first, then assigned, and then usedBasic Data type: 4 Class 8

Hangzhou Electric 2015 Postgraduate examination of Computer College second interview written first question Java solutionImport Java.util.scanner;import java.util.regex.matcher;import java.util.regex.pattern;/* Hangzhou 2015 Computer College re-examination pen first question JAV A solution * Author Liu Wangyang QQ 605283073 * Find out: Strings such as: "34223abd#

Java --------------- String basic interview questions Package stu. love. a;/* String: */public class StringDemo {public static void main (String [] args) {// the String is a constant. Once a String is created, the String ss = "hello"; ss = "world"; System. out. println (ss); // special case:/* when defining s2, go to the constant pool to check whether the string "1000phone" exists. If the constant pool alr

1. The difference between String and StringBufferThe Java platform provides two classes: string and StringBuffer, which can store and manipulate strings, That is, character data that contains more than one character. This string class provides values that cannot be changed strings and the strings provided by this Str

=============================================== finishing the 15-year school recruit interview topic, haven't had time to tidy up the Answer. The reference is of little significance. Only for RECORDS. =============================================== a White: 1. Java Multithreaded Programming 2. Session and Cookie concepts as well as use of 3. The concept of indexing in MySQL 4. The use of join in MySQL is 5.

Linkedhashmap traverse speed is only related to the actual data, and the capacity is independent, and HashMap's traverse speed is related to his capacity13, collection package structure, and the difference between collectionsCollection is a top-level interface of a collection class, and its direct inheritance interface has list and setCollections is a tool class/helper class for the collection class, which provides a series of static methods for sorting, searching, and line Cheng of elements in

and primitive types (or built-in types). int is the raw data type of Java, and integer is the wrapper class provided by Java for Int. Java provides a wrapper class for each primitive type.Raw type Encapsulation classBooleanbooleanCharcharacterBytebyteShortshortIntintegerLonglongFloatfloatDoubledoubleThe behavior of reference types and primitive types is complete

1. The size of the nine basic data types, as well as their encapsulation class.2. Can switch use string to make arguments?Answer: Swith can use parameter types in the Java language: only convertible int values, strings or enum variables is permittedcan be automatically converted to an integer type (byte,short,int), a string type, an enumeration type.Java cannot be a boolean,float,double,long of the switch p

and attribute value), and information about the server (by passing a ServletContext object)1, with 1-5 working experience, in the face of the current popular technology do not know where to start, the need to break through the technical bottlenecks can add group.2, in the company for a long time, live very comfortable, but job-hopping when the interview hit the Wall. Need to study in a short time, job-hopping to get high salaries can add group.3, if

2. How to determine whether 2 strings have the same character composition such as "AAAABBC" and "ABCBAAA"2 Kinds of ideasImport Java.lang.reflect.array;import java.util.arrays;//thought one: First sort 2 strings, in comparison, the so-called 2 string equal refers to the number of letters and numbers that make up a string, The order can be different public class Thesamestring {public static void compare (Str

break the box?X is an object, and what you do here is actually x.intvalue ().It is important to note that if you want to use the new feature after version 1.5. , you need to be aware of the value range of x, and the integer object x will have one more null value: null. A null pointer exception appears. Make an empty operation.Small case:Integer m = 128;Integer n = 128;Integer a = 127;Integer B = 127;M==n falseA==b trueThe first one is false or because M and n are different objects.The second tr

Ref property. byname: Automatically assembled by the parameter name, the spring container discovers that the bean's Autowire property is set to ByName in the configuration file, and then the container tries to match, assemble, and bean whose attributes have the same name. bytype:: With automatic assembly of parameter types, the spring container discovers that the bean's Autowire property is set to Bytype in the configuration file, after which the container tries to match, assemble, and

use the equal () method to determine equality must have the same hash code.Note:①hash code is a way of encoding, and in Java each object has a hashcode,java that can be used to identify an object by this hashcode.②equlas are mostly used to make string comparisons, and to determine the basic data type or object type, you need to use = =002. Strings=new string ("x

The basis of the data structure in the Java interview book-linear table Author: Egg Email: xtfggef@gmail.com Weibo: http://weibo.com/xtfggef Blog: http://blog.csdn.net/zhangerqing (reprinted please explain the source) As the most basic knowledge of computer science, this part of content is selected by almost all enterprises for examination. Therefore, we will explain the data structure from the basic aspect

Unicode to pass the interaction, there will be garbled, and vice versa.4.Convert string to bytes, various encoding conversion to bytes different, such as UTF-8 each Chinese character to 3bytes, and GBK to 2bytes, so to explain the encoding method, otherwise with the default encoding. is to convert a string of type strings to byte and into a byte array. All the data in Java is in bytes, and byte data can be

Look directly at the code.Package gdk.ware;Import Java.text.SimpleDateFormat;Import Java.util.Date;Import Java.util.HashMap;Import Java.util.Map.Entry;Import Org.testng.annotations.Test;Traversal of Map@Testpublic class Newhashmap {Static hashmapTraversepublic static void Main (){System.out.println ("Start traversal");For (String Key:map.keySet ()){System.out.println ("key:" + key + ", value=" +map.get (key));}Traversal Method 2SYSTEM.OUT.PRINTLN ("Traverse map via Map.entryset");For (entrySyste