{"id":5170,"date":"2021-03-23T11:36:26","date_gmt":"2021-03-23T11:36:26","guid":{"rendered":"https:\/\/ded9.com\/?p=5170"},"modified":"2025-12-27T13:22:53","modified_gmt":"2025-12-27T13:22:53","slug":"learning-comments-in-java-in-quite-simple-language","status":"publish","type":"post","link":"https:\/\/ded9.com\/tr\/learning-comments-in-java-in-quite-simple-language\/","title":{"rendered":"Learning Comments in Java in Quite Simple Language"},"content":{"rendered":"

In this tutorial, you will learn about comments in Java and why and how to use them.<\/span><\/span><\/p>\n

In programming, comments are considered part of the program and are used to aid understanding of the code. However, Java compilers<\/a> completely ignore them and do not execute them<\/span><\/span>.<\/span><\/p>\n

So in the Java programming language, there are two types of comments:<\/p>\n

\n
\/ *\u2026 * \/\r\n\/\/\u2026.<\/pre>\n<\/div>\n
Common comment \/*\u2026\u2026.*\/<\/span><\/h2>\n
\"Common<\/span><\/h1>\n
This is a multi-line comment. The Java compiler ignores everything from \/* to *\/. For example,<\/p>\n
\n
    \n
  1. \/ * This is a multi-line comment.<\/li>\n
  2. * The problem prints \u201cHello, World!\u201d\u00a0to the standard output.<\/li>\n
  3. * \/<\/li>\n
  4. class HelloWorld {<\/li>\n
  5. public static void main (String [] args) {<\/li>\n
  6. {<\/li>\n
  7. System.out.println (\u201cHello, World!\u201d);<\/li>\n
  8. }<\/li>\n
  9. }<\/li>\n
  10. }<\/li>\n<\/ol>\n<\/blockquote>\n
    In the above code, the comment is equal to:<\/p>\n
    \n
    \/ * This is a multi-line comment.\r\n\r\n* The problem prints \u201cHello, World!\u201d to the standard output.\r\n\r\n* \/<\/pre>\n<\/div>\n
    One line comment \/\/<\/span><\/h2>\n
    The compiler ignores everything from \/\/ to the bottom of the line.\u00a0For example,<\/p>\n
    \n
      \n
    1. \/\/ \u201cHello, World!\u201d\u00a0program<\/li>\n
    2. <\/li>\n
    3. class AssignmentOperator {<\/li>\n
    4. public static void main (String [] args) {<\/li>\n
    5. {<\/li>\n
    6. System.out.println (\u201cHello, World!\u201d);\u00a0\/\/ prints \u201cHello, World!\u201d<\/li>\n
    7. }<\/li>\n
    8. }<\/li>\n
    9. }<\/li>\n<\/ol>\n<\/blockquote>\n
      The above program includes two one-line comments:<\/p>\n
      \n
      \/\/\"Hello, World!\u201d\"program\r\n\r\nAnd\r\n\r\n\/\/ prints \"Hello, World!\"<\/pre>\n<\/div>\n
      Use the comments in the right way<\/h2>\n
      Comments should not be a substitute for explaining poorly written code in English. Write code with good structure and readability, and use comments.<\/p>\n
      Some believe the code should be documented and include a few comments. However, we strongly oppose this (this is our personal opinion). There is no problem with using comments to explain complex algorithms, regex, or scenarios.<\/p>\n
      Use comments to explain “why” instead of “how.”<\/p>\n
      Types of Java Comments<\/span><\/h2>\n
      \"Types<\/span><\/h2>\n
      Commenting code is a good practice for Java developers, enhancing code readability and maintainability. Java provides three types of comments:<\/p>\n
        \n
      1. Inline (Single-line) Comments<\/strong> \u2192 \/\/<\/code><\/li>\n
      2. Block (Multi-line) Comments<\/strong> \u2192 \/* ... *\/<\/code><\/li>\n
      3. JavaDoc Comments<\/strong> \u2192 \/** ... *\/<\/code><\/li>\n<\/ol>\n
        Inline Comments (<\/strong>\/\/<\/code>)<\/strong><\/h3>\n
        Also known as single-line comments, inline comments start with \/\/<\/code> and affect only the code on that line.<\/p>\n
        Example:<\/p>\n
        \n
        \n
        \n
        public class JavaCommentsExample {\r\n  \/\/ This is a single-line comment\r\n\r\n  public static void main(String[] args) {\r\n    System.out.println(\"This line will run.\");\r\n    \/\/System.out.println(\"This line will not run.\");\r\n  }\r\n}\r\n<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n
        Sometimes, inline comments are placed at the end of a line to clarify a variable or operation:<\/p>\n
        \n
        \n
        \n
        int number = 10;  \/\/ Initialize number to 10\r\n<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n
        Block Comments (<\/strong>\/* ... *\/<\/code>)<\/strong><\/span><\/h3>\n
        Block or multi-line comments allow developers to comment out multiple lines at once. This is useful for temporarily turning off code or adding detailed explanations.<\/p>\n
        Example:<\/p>\n
        \n
        \n
        \n
        public class JavaCommentsExample {\r\n  \/* This block comment spans one line. *\/\r\n  public static void main(String[] args) {\r\n    System.out.println(\"This line will run.\");\r\n\r\n    \/* This block comment spans multiple lines.\r\n       System.out.println(\"These lines will not run.\");\r\n       None of the code in this block comment will be executed.\r\n    *\/\r\n  }\r\n}\r\n<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n
        JavaDoc Comments (<\/strong>\/** ... *\/<\/code>)<\/strong><\/span><\/h3>\n
        JavaDoc comments are designed explicitly to generate documentation. Unlike inline or block comments, which are meant for developers maintaining the code, JavaDoc comments help users<\/strong> understand how to use a class or method.<\/p>\n
        Example:<\/p>\n
        \n
        \n
        \n
        \/** This JavaDoc comment describes the class. *\/\r\npublic class JavaCommentsExample {\r\n\r\n  \/** This JavaDoc comment describes the method. *\/\r\n  public static void main(String[] args) {\r\n    System.out.println(\"This line will run.\");  \/\/ Inline comment\r\n    \/* System.out.println(\"This is in a block comment.\"); *\/\r\n  }\r\n}\r\n<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n
        Best Practices for Using Java Comments<\/strong><\/span><\/h2>\n