PHP and Java are two languages, right?

This article explains what languages ​​​​are PHP and java respectively, so that friends can distinguish them. I hope it will be helpful to everyone.

Programming paradigm:

Java: A purely object-oriented language. Someone has said: Everything in Java is an object! Of course, people have forgotten Java's eight basic data types: int, double, boolean, byte, float, long, short, char. But on the basis that every basic data type in Java has a wrapper class (the wrapper class of int is Integer), let's just think that everything is an object.

PHP: Both object-oriented programming and process-oriented programming can be used. This language that combines two programming paradigms represents a future development trend of computer languages, and is reflected in Scala, Golang, and Python.

Language type:

Java: Java is a compiled and strongly typed language (or a statically typed language). Variables must declare types, for example: "int i = 0;" The language will be more rigorous and less error-prone, which is more beneficial to the long-term development and maintenance of very large projects with relatively long development cycles. Java source files need to be compiled into class files by the java compiler. Although from the perspective of the JVM, strictly speaking, java can also be called an "interpreted" language, because after all, it is the JVM that interprets the class files, but after all, it still goes through It is not compiled by the Java compiler, and it is directly compiled into a binary bytecode file, so it is not serious. It is considered a compiled type.

PHP: PHP is an interpreted weakly typed language (or a dynamically typed or non-statically typed language). Variables do not have to declare types, for example: "$i = 0;" This language will be easier to write. Comfortable, allows people to focus more on business logic, and helps improve development efficiency. The PHP file is called a "PHP script file". It is not compiled, but is interpreted directly by the PHP interpreter, so it is a non-compiled interpreted language.

Compiled static languages ​​that use "half-weak and half-strong" automatic type judgment at compile time are currently popular. For example: Golang, swift, Scala, etc.

Basic syntax such as control statement expression basic types:

The basic syntax of Java and PHP is basically the same. In fact, the basic syntax of most languages ​​​​is also the same, but They still have some subtle differences:

1. foreach statement:

The foreach statement in PHP is the same as most languages, it is a regular foreach: foreach($arrays as $elem){ $elem...} . But Java does not have the keyword "foreach" at all. Instead, it is "for". Someone also gave it a nice name "enhanced for loop", which is actually the foreach statement: for (String elem: arrays) {elem.. .}.

2. goto statement:

This keyword exists in Java, but in practice, it is not used. Instead, use continue or break to replace this keyword; however, it does not appear much in PHP, but it is used normally.

Java:

less:                                                                               
    for(int i=0;i<10;i++) 
    { 

      ........
      break less; 
     }

PHP:

less:                                                                               
    for($i=0;$i<10;$i++) 
    { 

      ........
     goto less; 
     }

3. Basic data types:

Java is int, double, boolean, byte, float, long, short, char;

php is a scalar type similar to Java: int, float, boolean, string. However, php also classifies arrays and objects as basic data types. Not only that, resource And NULL too.

The basic types of the language are not all scalar types such as int and double, but may also include other composite types or special types such as sets. For example, Golang uses map array as a basic type.

The above is the detailed content of PHP and Java are two languages, right?. For more information, please follow other related articles on the PHP Chinese website!