{"id":5274,"date":"2021-03-23T16:38:35","date_gmt":"2021-03-23T16:38:35","guid":{"rendered":"https:\/\/ded9.com\/?p=5274"},"modified":"2025-12-13T13:08:29","modified_gmt":"2025-12-13T13:08:29","slug":"complete-tutorial-for-builders-in-java-in-simple-language","status":"publish","type":"post","link":"https:\/\/ded9.com\/tr\/complete-tutorial-for-builders-in-java-in-simple-language\/","title":{"rendered":"Complete Tutorial for Builders in Java Explained Simply"},"content":{"rendered":"

In this tutorial, you will get acquainted with builders in Java <\/a>and learn how\u00a0to create and use builders with the help of examples.<\/span><\/span><\/p>\n

What is a Builder?<\/span><\/h2>\n

\"What<\/span><\/h1>\n

The constructor is similar to the method (but not the technique) that is called immediately when the object is created.<\/p>\n

The Java compiler distinguishes between a method and a constructor by their names and return types. In Java, the constructor has a class-like name and returns no values.<\/p>\n

\n
class Test {\r\n\r\nTest () {\r\n\r\n\/\/ constructor body\r\n\r\n}\r\n\r\n}<\/pre>\n<\/div>\n
Here, Test () is constructive. It has the same class name and no return type.<\/p>\n
\n
class Test {\r\n\r\nvoid Test () {\r\n\r\n\/\/ method body\r\n\r\n}\r\n\r\n}<\/pre>\n<\/div>\n
Here, Test () has the same name as the class.\u00a0However, its return type is void.\u00a0Hence, it is not constructive but methodical.<\/p>\n
Example: Builder in Java<\/strong><\/p>\n
\n
    \n
  1. class ConsMain {<\/li>\n
  2. private int x;<\/li>\n
  3. \/\/ constructor<\/li>\n
  4. private ConsMain () {<\/li>\n
  5. System.out.println (\u201cConstructor Called\u201d);<\/li>\n
  6. x = 5;<\/li>\n
  7. }<\/li>\n
  8. public static void main (String [] args) {<\/li>\n
  9. ConsMain obj = new ConsMain ();<\/li>\n
  10. System.out.println (\u201cValue of x =\u201d + obj.x);<\/li>\n
  11. }<\/li>\n
  12. }<\/li>\n<\/ol>\n<\/blockquote>\n
    Output<\/p>\n
    \n
    Constructor Called<\/p>\n
    Value of x = 5<\/p>\n<\/blockquote>\n
    Here, the ConsMain () constructor is called when the obj object is created.<\/p>\n
    A constructor may or may not accept an argument.<\/p>\n
    Builder without arguments<\/h2>\n
    If a Java constructor accepts no parameters, it is a no-argument constructor. Its structure is as follows:<\/p>\n
    \n
    accessModifier ClassName () {\r\n\r\n\/\/ constructor body\r\n\r\n}<\/pre>\n<\/div>\n
    Sample constructor without arguments<\/strong><\/p>\n
    \n
      \n
    1. class NoArgCtor {<\/li>\n
    2. int i;<\/li>\n
    3. \/\/ constructor with no parameter<\/li>\n
    4. private NoArgCtor () {<\/li>\n
    5. i = 5;<\/li>\n
    6. System.out.println (\u201cObject created and i =\u201d + i);<\/li>\n
    7. }<\/li>\n
    8. public static void main (String [] args) {<\/li>\n
    9. NoArgCtor obj = new NoArgCtor ();<\/li>\n
    10. }<\/li>\n
    11. }<\/li>\n<\/ol>\n<\/blockquote>\n
      Output<\/p>\n
      \n
      Object created and i = 5<\/p>\n<\/blockquote>\n
      Here, the NoArgCtor () constructor does not accept any parameters.<\/p>\n
      Did you notice that the creator of NoArgCtor () is private?<\/strong><\/p>\n
      This is because the object is made from within the same class.\u00a0Hence, it can access the manufacturer.<\/p>\n
      However, if the object is created outside of class, you must make access to that constructor public.\u00a0For example:<\/p>\n
      \n
        \n
      1. class Company {<\/li>\n
      2. String domainName;<\/li>\n
      3. \/\/ object is created in another class<\/li>\n
      4. public Company () {<\/li>\n
      5. domainName = \u201cprogramiz.com\u201d;<\/li>\n
      6. }<\/li>\n
      7. }<\/li>\n
      8. public class CompanyImplementation {<\/li>\n
      9. <\/li>\n
      10. public static void main (String [] args) {<\/li>\n
      11. Company companyObj = new Company ();<\/li>\n
      12. System.out.println (“Domain name =” + companyObj.domainName);<\/li>\n
      13. }<\/li>\n
      14. }<\/li>\n<\/ol>\n<\/blockquote>\n
        Output<\/p>\n
        \n
        Domain name = programiz.com<\/p>\n<\/blockquote>\n
        Default builder<\/span><\/h2>\n
        The Java compiler automatically creates an argument-free constructor at runtime if you do not make one. This builder is the default. The default constructor initializes each informal sample variable.<\/p>\n
        \"The<\/p>\n
        Example: Default builder<\/strong><\/p>\n
        \n
          \n
        1. class DefaultConstructor {<\/li>\n
        2. int a;<\/li>\n
        3. boolean b;<\/li>\n
        4. public static void main (String [] args) {<\/li>\n
        5. DefaultConstructor obj = new DefaultConstructor ();<\/li>\n
        6. System.out.println (\u201ca =\u201d + obj.a);<\/li>\n
        7. System.out.println (\u201cb =\u201d + obj.b);<\/li>\n
        8. }<\/li>\n
        9. }<\/li>\n<\/ol>\n<\/blockquote>\n
          The above program is equivalent to:<\/p>\n
          \n
            \n
          1. class DefaultConstructor {<\/li>\n
          2. int a;<\/li>\n
          3. boolean b;<\/li>\n
          4. private DefaultConstructor () {<\/li>\n
          5. a = 0;<\/li>\n
          6. b = false;<\/li>\n
          7. }<\/li>\n
          8. public static void main (String [] args) {<\/li>\n
          9. DefaultConstructor obj = new DefaultConstructor ();<\/li>\n
          10. System.out.println (\u201ca =\u201d + obj.a);<\/li>\n
          11. System.out.println (\u201cb =\u201d + obj.b);<\/li>\n
          12. }<\/li>\n
          13. }<\/li>\n<\/ol>\n<\/blockquote>\n
            Output<\/p>\n
            \n
            a = 0<\/p>\n
            b = false<\/p>\n<\/blockquote>\n
            Parametric constructor<\/h2>\n
            A constructor may also accept parameters. Its structure is as follows:<\/p>\n
            \n
            accessModifier ClassName (arg1, arg2,\u2026, argn) {\r\n\r\n\/\/ constructor body\r\n\r\n}<\/pre>\n<\/div>\n
            Example: Parametric constructor<\/strong><\/p>\n
            \n
              \n
            1. class Vehicle {<\/li>\n
            2. int wheels;<\/li>\n
            3. private Vehicle (int wheels) {<\/li>\n
            4. wheels = wheels;<\/li>\n
            5. System.out.println (wheels + \u201dwheeler vehicle created.\u201d);<\/li>\n
            6. }<\/li>\n
            7. public static void main (String [] args) {<\/li>\n
            8. Vehicle v1 = new Vehicle (2);<\/li>\n
            9. Vehicle v2 = new Vehicle (3);<\/li>\n
            10. Vehicle v3 = new Vehicle (4);<\/li>\n
            11. }<\/li>\n
            12. }<\/li>\n<\/ol>\n<\/blockquote>\n
              Output<\/p>\n
              \n
              2 wheeler vehicle created.<\/p>\n
              3 wheeler vehicle created.<\/p>\n
              4 wheeler vehicle created.<\/p>\n<\/blockquote>\n
              We passed an int (number of wheels) argument to the constructor when creating the object.<\/p>\n
              Overload<\/a> builders in Java<\/h2>\n
              As with method overloading, you can have two or more manufacturers with the same name and parameters. For example:<\/p>\n
              \n
                \n
              1. class Company {<\/li>\n
              2. String domainName;<\/li>\n
              3. public Company () {<\/li>\n
              4. this.domainName = \u201cdefault\u201d;<\/li>\n
              5. }<\/li>\n
              6. public Company (String domainName) {<\/li>\n
              7. this.domainName = domainName;<\/li>\n
              8. }<\/li>\n
              9. public void getName () {<\/li>\n
              10. System.out.println (this.domainName);<\/li>\n
              11. }<\/li>\n
              12. public static void main (String [] args) {<\/li>\n
              13. Company defaultObj = new Company ();<\/li>\n
              14. Company programizObj = new Company (\u201cprogramiz.com\u201d);<\/li>\n
              15. defaultObj.getName ();<\/li>\n
              16. programizObj.getName ();<\/li>\n
              17. }<\/li>\n
              18. }<\/li>\n<\/ol>\n<\/blockquote>\n
                Output<\/p>\n
                \n
                default<\/p>\n
                programiz.com<\/p>\n<\/blockquote>\n
                important points<\/h2>\n
                  \n
                • Immediately after calling the objects, the creators are called.<\/li>\n
                • The two laws of creation are:<\/li>\n
                • The Java constructor name must match the class name exactly.<\/li>\n
                • A Java constructor should not have a recursive type.<\/li>\n
                • If a class does not have a constructor, the Java compiler automatically generates a default constructor at runtime. The default constructor initializes the sample variables with the default values. For example, the variable int is equal to 0.<\/li>\n
                • Manufacturer types:<\/li>\n
                • No-Arg Constructor – A constructor that accepts no arguments<\/li>\n
                • Default Builder – A builder created automatically by a Java compiler.\u00a0(If not explicitly defined)<\/li>\n
                • Parametric constructor – Used to specify specific values \u200b\u200bof variables in an object<\/li>\n
                • Creators cannot be abstract, static, or final.<\/li>\n
                • The constructor can be defined several times.<\/li>\n<\/ul>\n
                  FAQ<\/h2>\n
                  \n
                  \n
                  \n
                  What is the Builder pattern in Java?<\/h3>\n
                  \n\n
                  It is a design pattern used to construct complex objects step by step without using multiple constructors.<\/p>\n\n<\/div>\n<\/div>\n
                  \n
                  Why should developers use builders in Java?<\/h3>\n
                  \n\n
                  Builders improve code readability, reduce constructor overload, and make object creation more flexible.<\/p>\n\n<\/div>\n<\/div>\n
                  \n
                  When is the Builder pattern most useful?<\/h3>\n
                  \n\n
                  It is useful when an object has many optional parameters or complex construction logic.<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"
                  In this tutorial, you will get acquainted with builders in Java and learn how\u00a0to create and use builders with the help of examples. What is a Builder? The constructor is similar to the method (but not the technique) that is called immediately when the object is created. The Java compiler distinguishes between a method and […]<\/p>\n","protected":false},"author":6,"featured_media":257966,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[11513],"tags":[840],"class_list":["post-5274","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-java-2","tag-java"],"acf":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/posts\/5274","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/comments?post=5274"}],"version-history":[{"count":6,"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/posts\/5274\/revisions"}],"predecessor-version":[{"id":266117,"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/posts\/5274\/revisions\/266117"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/media\/257966"}],"wp:attachment":[{"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/media?parent=5274"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/categories?post=5274"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ded9.com\/tr\/wp-json\/wp\/v2\/tags?post=5274"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}