Page 47-JavaBase Programming Tutorials: Learn JavaBase Online-php.cn

Article Tags

Home

Technical Articles

Java

JavaBase

Solution to garbled url in java

Solution to garbled URLs in Java: Use the encode() or encodeURI() method to convert Chinese characters into hexadecimal characters before passing parameters. After receiving the parameters, use the decode() method to convert hexadecimal characters into Chinese to solve the URL garbled problem.

Dec 03, 2019 am 10:29 AM

java

What is file in java?

File in java is a file class that can be used to add, delete, and search for certain types of files or folders. At the same time, it can be comprehensively utilized according to the characteristics of its member variables to avoid errors across systems, and it is best to enter when searching. Absolute path to avoid non-existent files.

Dec 03, 2019 am 10:15 AM

java

Reasons and solutions for 400 errors reported in Java projects

Reasons why Java projects report 400 errors: 1. The field names or types submitted in the front end are inconsistent with those in the backend, resulting in 400 errors. 2. The front end did not convert the submitted object into a string. Solution: 1. Ensure that the field name types are consistent. 2. Convert the object passed by the front end into a string.

Dec 03, 2019 am 10:08 AM

Java

Detailed explanation of the method of judging whether it is a number in java

How to determine whether it is a number in Java: 1. First define the regular expression "[0-9]*", and then use the matcher() method to match the regular expression to determine whether it is a number. 2. Use the isDigit() function to determine. 3. Determine whether a character is a digit or not by its ASCII code value.

Dec 03, 2019 am 09:54 AM

java

How to export Excel from Java

How to export Excel in Java: You can use the Jakarta POI HSSF API component in java to implement Excel export. 1. Use HSSWorkbook to create Excel file objects and sheet objects. 2. Return the row object and get the cell object. 3. Use cell objects to read and write.

Dec 03, 2019 am 09:44 AM

Java

How to get input in java?

Methods to obtain input in java: 1. Use the System.in.read() method to obtain the input characters from the console. 2. Use the BufferedReader class and the InputStreamReader class to get the input string from the console. 3. Use the Scanner class to obtain input.

Dec 03, 2019 am 09:21 AM

java

The difference between overloading and rewriting in java

The difference between overloading and rewriting in Java: 1. Overloading means that different functions use the same function name, but the number or type of parameters of the function is different. Overriding refers to reimplementing the virtual functions in the base class in the derived class. 2. The relationship between the two and the class is different. 3. The two have different requirements for parameter lists.

Dec 02, 2019 pm 04:05 PM

java

Solution to Java reading oracle garbled code

Solution to garbled characters read from Oracle in java: 1. Transcode the read string, transcoding method: "String(s.getByte(A),B)". 2. Use Druid for transcoding, which provides a unified package for various database drivers and adds functions such as logging, alarms, and encoding conversion.

Dec 02, 2019 pm 03:25 PM

java 乱码

What is a package in java?

In order to better organize classes, Java provides a package mechanism to distinguish namespaces of class names. Java uses the package mechanism to prevent naming conflicts, access control, provide search and location of classes, interfaces, enumerations and annotations, etc.

Dec 02, 2019 pm 03:15 PM

java

The difference between double and float in java

The difference between double and float in Java: 1. The number of bytes occupied in memory is different: double occupies 8 bytes and float occupies 4 bytes. 2. The number of significant digits is different: double has 16 significant digits, and float has 8 significant digits. 3. The range of numbers that can be expressed is different.

Dec 02, 2019 pm 02:51 PM

java

What does final mean in Java?

Final in Java is a keyword that can be used to modify references, methods and classes. When used to modify a reference, the referenced value or address cannot be modified. When used to modify a method, this method will become the final method and cannot be overridden by subclasses. When used to modify a class, the class becomes final and cannot be inherited.

Dec 02, 2019 pm 02:38 PM

Java final

Can java sort letters?

Java can sort alphabetically. In java, first use the substring() method to intercept the letters in the string and save them into the list collection, and then use the sort() method in the java.util.Collections class to sort the letters in the list collection.

Dec 02, 2019 pm 02:24 PM

java

What is the difference between java character stream and byte stream

The difference between character stream and byte stream in Java: 1. The basic unit of byte stream operation is byte, and the basic unit of character stream operation is Unicode code element. 2. The byte stream does not use the buffer by default, and the character stream uses the buffer. 3. Character streams usually process text data, and byte streams usually process binary data.

Dec 02, 2019 pm 02:10 PM

java 字符流字节流

Introduction to the method of judging whether a string is time in java

How to determine whether a string is time in java: first add the date and time format to parsePatterns, and then call the parseDate method to determine whether the string is time through the date and time format in parsePatterns.

Dec 02, 2019 pm 01:55 PM

java