{"id":159660,"date":"2019-07-10T02:54:00","date_gmt":"2019-07-09T18:54:00","guid":{"rendered":"http:\/\/itteacheritfreelance.hk\/test\/wordpress\/?guid=4b858541f12221facd8bda008d4e7483"},"modified":"2019-07-10T02:54:00","modified_gmt":"2019-07-09T18:54:00","slug":"class-and-object-initialization-in-java","status":"publish","type":"post","link":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/2019\/07\/10\/class-and-object-initialization-in-java\/","title":{"rendered":"Class and object initialization in Java"},"content":{"rendered":"<article>\n<section class=\"page\">\n<p>Classes and objects in Java must be initialized before they are used. You&#8217;ve <a href=\"http:\/\/www.javaworld.com\/article\/2979739\/learn-java\/java-101-classes-and-objects-in-java.html\" rel=\"noopener\" >previously learned<\/a> that <a href=\"http:\/\/itteacheritfreelance.hk\/index.php\" title=\"\u672c\u7db1\u9801\u63d0\u4f9b\u4e00\u500b\u65b9\u4fbf\u7684\u5e73\u53f0, \u70ba\u5927\u5bb6\u914d\u5c0d\u96fb\u8166\u88dc\u7fd2,IT freelance, \u79c1\u4eba\u8001\u5e2b , PHP\u88dc\u7fd2, HTML\u88dc\u7fd2, CSS\u88dc\u7fd2, JavaScript\u88dc\u7fd2, XML, Java\u88dc\u7fd2,Server\u88dc\u7fd2, MySQL\u88dc\u7fd2, \u4e2d\u5b78\u96fb\u8166\u79d1\u79c1\u4eba\u88dc\u7fd2, \u5728\u8077\u4eba\u58eb\u96fb\u8166\u63d0\u5347\u88dc\u7fd2,\u5c08\u696d\u8003\u8a66\u96fb\u8166 \u88dc\u7fd2,\u96fb\u8166\u5716\u50cf\u8a2d\u8a08\u96fb\u8166\u88dc\u7fd2, gra\">class<\/a> fields are initialized to default values when <a href=\"http:\/\/itteacheritfreelance.hk\/index.php\" title=\"\u672c\u7db1\u9801\u63d0\u4f9b\u4e00\u500b\u65b9\u4fbf\u7684\u5e73\u53f0, \u70ba\u5927\u5bb6\u914d\u5c0d\u96fb\u8166\u88dc\u7fd2,IT freelance, \u79c1\u4eba\u8001\u5e2b , PHP\u88dc\u7fd2, HTML\u88dc\u7fd2, CSS\u88dc\u7fd2, JavaScript\u88dc\u7fd2, XML, Java\u88dc\u7fd2,Server\u88dc\u7fd2, MySQL\u88dc\u7fd2, \u4e2d\u5b78\u96fb\u8166\u79d1\u79c1\u4eba\u88dc\u7fd2, \u5728\u8077\u4eba\u58eb\u96fb\u8166\u63d0\u5347\u88dc\u7fd2,\u5c08\u696d\u8003\u8a66\u96fb\u8166 \u88dc\u7fd2,\u96fb\u8166\u5716\u50cf\u8a2d\u8a08\u96fb\u8166\u88dc\u7fd2, gra\">class<\/a>es are loaded and that objects are initialized via <a href=\"http:\/\/itteacheritfreelance.hk\/index.php\" title=\"\u672c\u7db1\u9801\u63d0\u4f9b\u4e00\u500b\u65b9\u4fbf\u7684\u5e73\u53f0, \u70ba\u5927\u5bb6\u914d\u5c0d\u96fb\u8166\u88dc\u7fd2,IT freelance, \u79c1\u4eba\u8001\u5e2b , PHP\u88dc\u7fd2, HTML\u88dc\u7fd2, CSS\u88dc\u7fd2, JavaScript\u88dc\u7fd2, XML, Java\u88dc\u7fd2,Server\u88dc\u7fd2, MySQL\u88dc\u7fd2, \u4e2d\u5b78\u96fb\u8166\u79d1\u79c1\u4eba\u88dc\u7fd2, \u5728\u8077\u4eba\u58eb\u96fb\u8166\u63d0\u5347\u88dc\u7fd2,\u5c08\u696d\u8003\u8a66\u96fb\u8166 \u88dc\u7fd2,\u96fb\u8166\u5716\u50cf\u8a2d\u8a08\u96fb\u8166\u88dc\u7fd2, gra\">constructor<\/a>s, but there is more to initialization. This article introduces all of Java&#8217;s features for initializing <a href=\"http:\/\/itteacheritfreelance.hk\/index.php\" title=\"\u672c\u7db1\u9801\u63d0\u4f9b\u4e00\u500b\u65b9\u4fbf\u7684\u5e73\u53f0, \u70ba\u5927\u5bb6\u914d\u5c0d\u96fb\u8166\u88dc\u7fd2,IT freelance, \u79c1\u4eba\u8001\u5e2b , PHP\u88dc\u7fd2, HTML\u88dc\u7fd2, CSS\u88dc\u7fd2, JavaScript\u88dc\u7fd2, XML, Java\u88dc\u7fd2,Server\u88dc\u7fd2, MySQL\u88dc\u7fd2, \u4e2d\u5b78\u96fb\u8166\u79d1\u79c1\u4eba\u88dc\u7fd2, \u5728\u8077\u4eba\u58eb\u96fb\u8166\u63d0\u5347\u88dc\u7fd2,\u5c08\u696d\u8003\u8a66\u96fb\u8166 \u88dc\u7fd2,\u96fb\u8166\u5716\u50cf\u8a2d\u8a08\u96fb\u8166\u88dc\u7fd2, gra\">class<\/a>es and objects.<\/p>\n<aside class=\"sidebar\">\n<p>Note that code examples in this tutorial compile and run under Java 12.<\/p>\n<\/aside>\n<h2>How to initialize a Java <a href=\"http:\/\/itteacheritfreelance.hk\/index.php\" title=\"\u672c\u7db1\u9801\u63d0\u4f9b\u4e00\u500b\u65b9\u4fbf\u7684\u5e73\u53f0, \u70ba\u5927\u5bb6\u914d\u5c0d\u96fb\u8166\u88dc\u7fd2,IT freelance, \u79c1\u4eba\u8001\u5e2b , PHP\u88dc\u7fd2, HTML\u88dc\u7fd2, CSS\u88dc\u7fd2, JavaScript\u88dc\u7fd2, XML, Java\u88dc\u7fd2,Server\u88dc\u7fd2, MySQL\u88dc\u7fd2, \u4e2d\u5b78\u96fb\u8166\u79d1\u79c1\u4eba\u88dc\u7fd2, \u5728\u8077\u4eba\u58eb\u96fb\u8166\u63d0\u5347\u88dc\u7fd2,\u5c08\u696d\u8003\u8a66\u96fb\u8166 \u88dc\u7fd2,\u96fb\u8166\u5716\u50cf\u8a2d\u8a08\u96fb\u8166\u88dc\u7fd2, gra\">class<\/a><\/h2>\n<p>Before we explore Java&#8217;s support for <a href=\"http:\/\/itteacheritfreelance.hk\/index.php\" title=\"\u672c\u7db1\u9801\u63d0\u4f9b\u4e00\u500b\u65b9\u4fbf\u7684\u5e73\u53f0, \u70ba\u5927\u5bb6\u914d\u5c0d\u96fb\u8166\u88dc\u7fd2,IT freelance, \u79c1\u4eba\u8001\u5e2b , PHP\u88dc\u7fd2, HTML\u88dc\u7fd2, CSS\u88dc\u7fd2, JavaScript\u88dc\u7fd2, XML, Java\u88dc\u7fd2,Server\u88dc\u7fd2, MySQL\u88dc\u7fd2, \u4e2d\u5b78\u96fb\u8166\u79d1\u79c1\u4eba\u88dc\u7fd2, \u5728\u8077\u4eba\u58eb\u96fb\u8166\u63d0\u5347\u88dc\u7fd2,\u5c08\u696d\u8003\u8a66\u96fb\u8166 \u88dc\u7fd2,\u96fb\u8166\u5716\u50cf\u8a2d\u8a08\u96fb\u8166\u88dc\u7fd2, gra\">class<\/a> initialization, let&#8217;s recap the steps of initializing a Java <a href=\"http:\/\/itteacheritfreelance.hk\/index.php\" title=\"\u672c\u7db1\u9801\u63d0\u4f9b\u4e00\u500b\u65b9\u4fbf\u7684\u5e73\u53f0, \u70ba\u5927\u5bb6\u914d\u5c0d\u96fb\u8166\u88dc\u7fd2,IT freelance, \u79c1\u4eba\u8001\u5e2b , PHP\u88dc\u7fd2, HTML\u88dc\u7fd2, CSS\u88dc\u7fd2, JavaScript\u88dc\u7fd2, XML, Java\u88dc\u7fd2,Server\u88dc\u7fd2, MySQL\u88dc\u7fd2, \u4e2d\u5b78\u96fb\u8166\u79d1\u79c1\u4eba\u88dc\u7fd2, \u5728\u8077\u4eba\u58eb\u96fb\u8166\u63d0\u5347\u88dc\u7fd2,\u5c08\u696d\u8003\u8a66\u96fb\u8166 \u88dc\u7fd2,\u96fb\u8166\u5716\u50cf\u8a2d\u8a08\u96fb\u8166\u88dc\u7fd2, gra\">class<\/a>. Consider Listing 1.<\/p>\n<p class=\"jumpTag\"><a href=\"https:\/\/www.javaworld.com\/article\/3040564\/java-101-class-and-object-initialization-in-java.html#jump\">To read this article in full, please click here<\/a><\/p>\n<\/section>\n<\/article>\n","protected":false},"excerpt":{"rendered":"<p>Classes and objects in Java must be initialized before they are used. You&#8217;ve previously learned that class fields are initialized to default values when classes are loaded and that objects are initialized via constructors, but there is more to initi&#8230; <a href=\"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/2019\/07\/10\/class-and-object-initialization-in-java\/\">\u95b1\u8b80\u5168\u6587 <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":123,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"slim_seo":[],"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[12,2,315,240],"tags":[398,402,397,414,413,528,410,409,407,408,406,399,400,394,318,526,375,523,183,184,529,524,232,10,401,396,381,403,412,411,395,405,404,525,457,530,363,384,321,320,319,316,26,527,317],"jetpack_publicize_connections":[],"aioseo_notices":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p7prtj-Fxa","jetpack-related-posts":[],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/posts\/159660"}],"collection":[{"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/users\/123"}],"replies":[{"embeddable":true,"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/comments?post=159660"}],"version-history":[{"count":2,"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/posts\/159660\/revisions"}],"predecessor-version":[{"id":160845,"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/posts\/159660\/revisions\/160845"}],"wp:attachment":[{"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/media?parent=159660"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/categories?post=159660"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itteacheritfreelance.hk\/test\/wordpress\/wp-json\/wp\/v2\/tags?post=159660"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}