In this tutorial, you will learn about nested static class with the help of examples. You will also learn about how static classes differs from inner classes.<\/p>\n\n\n\n
As learned in previous tutorials, we can have a class inside another class in Java. Such classes are known as nested classes. In Java, nested classes are of two types:<\/p>\n\n\n\n
We have already discussed inner classes in the previous tutorial. Visit\u00a0Java Nested Class\u00a0if you want to learn about inner classes.<\/p>\n\n\n\n
In this tutorial, we will learn about nested static classes.<\/p>\n\n\n\n
We use the keyword Note:<\/strong> In Java, only nested classes are allowed to be static.<\/p>\n\n\n\n Like regular classes, static nested classes can include both static and non-static fields and methods. For example,<\/p>\n\n\n\n Static nested classes are associated with the outer class.<\/p>\n\n\n\n To access the static nested class, we don\u2019t need objects of the outer class.<\/p>\n\n\n\n Output<\/strong><\/p>\n\n\n\n In the above program, we have two nested class Mammal<\/var> and Reptile<\/var> inside a class Animal<\/var>.<\/p>\n\n\n\n To create an object of the non-static class Reptile, we have used<\/p>\n\n\n\n To create an object of the static class Mammal<\/var>, we have used<\/p>\n\n\n\n In Java, static nested classes are associated with the outer class. This is why static nested classes can only access the class members (static fields and methods) of the outer class.<\/p>\n\n\n\n Let\u2019s see what will happen if we try to access non-static fields and methods of the outer class.<\/p>\n\n\n\n Output<\/strong><\/p>\n\n\n\n In the above example, we have created a non-static method Now, if we try to access It is because mammal<\/var> is an object of a static class and we cannot access non-static methods from static classes.<\/p>\n\n\n\n As mentioned above, only nested classes can be static. We cannot have static top-level classes.<\/p>\n\n\n\n Let\u2019s see what will happen if we try to make a top-level class static.<\/p>\n\n\n\n Output<\/strong><\/p>\n\n\n\n In the above example, we have tried to create a static class Animal<\/var>. Since Java doesn\u2019t allow static top-level class, we will get an error.<\/p>\n\n\n\n In this tutorial, you will learn about nested static class with the help of examples. You will also learn about how static classes differs from inner classes. As learned in previous tutorials, we can have a class inside another class in Java. Such classes are known as nested classes. In Java, nested classes are of […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[556],"tags":[],"_links":{"self":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/1218"}],"collection":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/comments?post=1218"}],"version-history":[{"count":0,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/1218\/revisions"}],"wp:attachment":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/media?parent=1218"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/categories?post=1218"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/tags?post=1218"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}static<\/code> to make our nested class static.<\/p>\n\n\n\nClass Animal {\n static class Mammal {\n \/\/ static and non-static members of Mammal\n }\n \/\/ members of Animal\n} \n<\/code><\/pre>\n\n\n\n
\n\n\n\nExample: Static Nested Class<\/h3>\n\n\n\n
class Animal {\n\n\/\/ inner class\n class Reptile {\n public void displayInfo() {\n System.out.println(\"I am a reptile.\");\n }\n }\n\n\/\/ static class\n static class Mammal {\n public void displayInfo() {\n System.out.println(\"I am a mammal.\");\n }\n }\n}\n\nclass Main {\n public static void main(String[] args) {\n \/\/ object creation of the outer class\n Animal animal = new Animal();\n\n \/\/ object creation of the non-static class\n Animal.Reptile reptile = animal.new Reptile();\n reptile.displayInfo();\n\n \/\/ object creation of the static nested class\n Animal.Mammal mammal = new Animal.Mammal();\n mammal.displayInfo();\n\n }\n}\n<\/code><\/pre>\n\n\n\nI am a reptile.\nI am a mammal.\n<\/samp><\/code><\/pre>\n\n\n\nAnimal.Reptile reptile = animal.new Reptile()\n<\/code><\/pre>\n\n\n\nAnimal.Mammal mammal = new Animal.Mammal()\n<\/code><\/pre>\n\n\n\n
\n\n\n\nAccessing Members of Outer Class<\/h2>\n\n\n\n
Example: Accessing Non-static members<\/h3>\n\n\n\n
class Animal {\n static class Mammal {\n public void displayInfo() {\n System.out.println(\"I am a mammal.\");\n }\n }\n\n class Reptile {\n public void displayInfo() {\n System.out.println(\"I am a reptile.\");\n }\n }\n\n public void eat() {\n System.out.println(\"I eat food.\");\n }\n}\n\nclass Main {\n public static void main(String[] args) {\n Animal animal = new Animal();\n Animal.Reptile reptile = animal.new Reptile();\n reptile.displayInfo();\n\n Animal.Mammal mammal = new Animal.Mammal();\n mammal.displayInfo();\n mammal.eat();\n }\n}\n<\/code><\/pre>\n\n\n\nMain.java:28: error: cannot find symbol\n mammal.eat();\n ^\n symbol: method eat()\n location: variable mammal of type Mammal\n1 error\ncompiler exit status 1\n<\/samp><\/code><\/pre>\n\n\n\neat()<\/code> inside the class Animal<\/var>.<\/p>\n\n\n\neat()<\/code> using the object mammal<\/var>, the compiler shows an error.<\/p>\n\n\n\n
\n\n\n\nStatic Top-level Class<\/h2>\n\n\n\n
static class Animal {\n public static void displayInfo() {\n System.out.println(\"I am an animal\");\n }\n}\n\nclass Main {\n public static void main(String[] args) {\n Animal.displayInfo();\n }\n}\n<\/code><\/pre>\n\n\n\nMain.java:1: error: modifier static not allowed here\nstatic class Animal {\n ^\n1 error\ncompiler exit status 1\n<\/samp><\/code><\/pre>\n\n\n\n<\/h3>\n","protected":false},"excerpt":{"rendered":"