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Java uses if statement to determine whether strings are equal

The way to use if statements in Java to determine whether strings are equal is: [if(s1.equals(s2))]. Since strings are object types, they cannot be judged by simple [==]. You need to use [equals]. Judgment, [equals] compares the contents of objects.

Dec 30, 2019 am 09:19 AM

if java judgment string

What is a member variable in java

In Java, member variables refer to variables defined in the variable part of the class body, also called attributes. Member variables are declared in the class, outside the method body, and are instantiated when the object is created; member variables can be accessed by methods, constructors in the class, and statement blocks of a specific class. If a member variable is not initialized when it is declared, the system will initialize the member variable with a default value.

Dec 28, 2019 pm 04:41 PM

java Member variables

How to solve the problem of garbled characters in exported csv files using Java

Solution to the garbled code in Java exported csv files: Files exported in CSV mode do not contain BOM information by default. This problem can be solved by setting the BOM identifier (byte stream starting with EF BB BF) for the content to be output.

Dec 28, 2019 pm 04:29 PM

java Garbled characters

How to determine whether a java object is empty

Methods to determine whether an object is empty in java: 1. Use the StringUtils class under the org.apache.commons.lang3 package to determine. 2. Use the Object class under the org.springframework.util package to judge.

Dec 28, 2019 pm 04:05 PM

java object

How to generate random numbers in java

In Java, you can use the random() method in the Math class to generate random numbers. The return value of the random() method is [0.0-1.0), that is, a random number between 0.0 and 1.0 is generated.

Dec 28, 2019 pm 03:41 PM

java

How to determine whether a specified character exists in java

In Java, you can use the contains method to determine whether the specified character exists. The java.lang.String.contains() method returns true if and only if this string contains the specified char value sequence.

Dec 28, 2019 pm 03:10 PM

java

How java is cross-platform

Methods for java to achieve cross-platform: 1. By specifying the value range and behavior of basic data types in the Java language. 2. Compile all java files into class files. 3. Convert the Class file into a binary file corresponding to the platform through the Java virtual machine.

Dec 28, 2019 pm 02:55 PM

java

Java determines whether a string contains the specified string

Java can use the indexOf(String s) method to determine whether a string contains the specified string. If it does, the returned value is the starting position of the substring in the parent string. If it does not contain, the entire return value must be -1. .

Dec 28, 2019 pm 02:19 PM

java string

How to compile java into class file

Method to compile java into class file: 1. Open cmd and enter the bin directory of jdk installation. 2. Then find the Java file to be compiled and use the Javac command to compile the java file into a class file.

Dec 28, 2019 pm 02:03 PM

java

Java determines whether a string is Chinese

How to determine whether a string is Chinese in java: You can use "string.matches("[\u4E00-\u9FA5]+")" to determine whether a string is Chinese. "\u4E00-\u9FA5" is the Chinese Unicode encoding range.

Dec 28, 2019 pm 01:31 PM

java string

What is the function of java method

A Java method is a collection of statements that together perform a function. The role of the java method: it can make the program shorter and clearer, improve the efficiency of program development, and improve the reusability of the code.

Dec 28, 2019 am 11:16 AM

java method

How to write a file in java

How to write files in java: 1. Use FileWritter to write files. The character stream writes characters to the file. By default, new content will be used to replace all existing content. 2. Use BufferedWriter to write files.

Dec 28, 2019 am 10:57 AM

java document

Java determines whether the database exists

Whether the Java database exists can be judged by using statements such as "String sql="SELECT COUNT(*) FROM information_schema.schemata WHERE schema_name=\""+database+"\""".

Dec 28, 2019 am 10:42 AM

java

How to use t in java

<T>T in Java means that the return value is a generic type, and a single T means to limit the parameter type you pass. It is mostly used to jointly operate a class object and then obtain the collection information inside.

Dec 28, 2019 am 10:04 AM

java