Iterator<\/h3>\n
public interface Iterator<E><\/p>\n
Iterator is an interface in the Java Collection framework that is used to iterate over a collection. An Iterator object enables us to traverse through a collection. We can get an Iterator for a collection by calling the iterator method.<\/p>\n
Code listing<\/h3>\nimport java.util.ArrayList;\r\nimport java.util.Iterator;\r\nimport java.util.List;\r\n\r\npublic class Demo {\r\n List<String> list = new ArrayList<String>();\r\n \r\n public Demo() {\r\n list.add(\"One\");\r\n list.add(\"Two\");\r\n list.add(\"Three\");\r\n list.add(\"Four\");\r\n list.add(\"Five\");\r\n }\r\n \r\n \/\/traverse method using Iterator\r\n public void traverse() {\r\n Iterator<String> itr= list.iterator();\r\n while(itr.hasNext()) {\r\n System.out.println(itr.next());\r\n }\r\n }\r\n \r\n public static void main(String[] args) {\r\n Demo d = new Demo();\r\n d.traverse();\r\n }\r\n}\r\n<\/pre>\n![\"Iterator](\"https:\/\/www.testingdocs.com\/questions\/wp-content\/uploads\/Iterator-collection.png\" "\\"\\"")
<\/p>\n
<\/p>\n
The hasNext() method returns true if the collection has more elements, and the next() method returns the next element in the collection. i.e list in this case.<\/p>\n
for-each loop<\/h3>\n
The for-each loop allows us to traverse a collection using an enhanced for loop. For Example, the following snippet uses the for-each loop to print out each element of a collection.<\/p>\n
import java.util.ArrayList;\r\nimport java.util.Iterator;\r\nimport java.util.List;\r\n\r\npublic class Demo {\r\n List<String> list = new ArrayList<String>();\r\n \r\n public Demo() {\r\n list.add(\"One\");\r\n list.add(\"Two\");\r\n list.add(\"Three\");\r\n list.add(\"Four\");\r\n list.add(\"Five\");\r\n }\r\n \r\n \/\/traverse method using for each\r\n public void traverse() {\r\n for(String str : list) {\r\n System.out.println(str);\r\n }\r\n }\r\n \r\n public static void main(String[] args) {\r\n Demo d = new Demo();\r\n d.traverse();\r\n }\r\n}\r\n<\/pre>\n <\/p>\n\n
\n <\/div>\n\n","protected":false},"excerpt":{"rendered":"Introduction We can traverse a collection of objects in Java by: using Iterators. using the for-each construct. Iterator public interface Iterator<E> Iterator is an interface in the Java Collection framework that is used to iterate over a collection. An Iterator object enables us to traverse through a collection. We can get an Iterator for a […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[40],"tags":[],"class_list":["post-4145","post","type-post","status-publish","format-standard","hentry","category-java","has-post-title","has-post-date","has-post-category","has-post-tag","has-post-comment","has-post-author",""],"_links":{"self":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts\/4145","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/comments?post=4145"}],"version-history":[{"count":3,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts\/4145\/revisions"}],"predecessor-version":[{"id":19743,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts\/4145\/revisions\/19743"}],"wp:attachment":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/media?parent=4145"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/categories?post=4145"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/tags?post=4145"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
<\/p>\n
<\/p>\n
The hasNext() method returns true if the collection has more elements, and the next() method returns the next element in the collection. i.e list in this case.<\/p>\n
for-each loop<\/h3>\n
The for-each loop allows us to traverse a collection using an enhanced for loop. For Example, the following snippet uses the for-each loop to print out each element of a collection.<\/p>\n
import java.util.ArrayList;\r\nimport java.util.Iterator;\r\nimport java.util.List;\r\n\r\npublic class Demo {\r\n List<String> list = new ArrayList<String>();\r\n \r\n public Demo() {\r\n list.add(\"One\");\r\n list.add(\"Two\");\r\n list.add(\"Three\");\r\n list.add(\"Four\");\r\n list.add(\"Five\");\r\n }\r\n \r\n \/\/traverse method using for each\r\n public void traverse() {\r\n for(String str : list) {\r\n System.out.println(str);\r\n }\r\n }\r\n \r\n public static void main(String[] args) {\r\n Demo d = new Demo();\r\n d.traverse();\r\n }\r\n}\r\n<\/pre>\n <\/p>\n\n
\n <\/div>\n\n","protected":false},"excerpt":{"rendered":"Introduction We can traverse a collection of objects in Java by: using Iterators. using the for-each construct. Iterator public interface Iterator<E> Iterator is an interface in the Java Collection framework that is used to iterate over a collection. An Iterator object enables us to traverse through a collection. We can get an Iterator for a […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[40],"tags":[],"class_list":["post-4145","post","type-post","status-publish","format-standard","hentry","category-java","has-post-title","has-post-date","has-post-category","has-post-tag","has-post-comment","has-post-author",""],"_links":{"self":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts\/4145","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/comments?post=4145"}],"version-history":[{"count":3,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts\/4145\/revisions"}],"predecessor-version":[{"id":19743,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/posts\/4145\/revisions\/19743"}],"wp:attachment":[{"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/media?parent=4145"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/categories?post=4145"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.testingdocs.com\/questions\/wp-json\/wp\/v2\/tags?post=4145"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}