{"id":346,"date":"2009-03-25T18:08:41","date_gmt":"2009-03-25T21:08:41","guid":{"rendered":"https:\/\/devkico.itexto.com.br\/?p=346"},"modified":"2009-03-29T11:55:57","modified_gmt":"2009-03-29T14:55:57","slug":"why-at-least-for-me-groovy-sounds-like-a-java","status":"publish","type":"post","link":"https:\/\/devkico.itexto.com.br\/?p=346","title":{"rendered":"Why (at least for me) Groovy sounds like a Java++"},"content":{"rendered":"

\"\"<\/a>I’m a Java guy, and as may sound obsolete to some, but I really like this language. As time goes by, and I start to know better another languages like Groovy or Ruby, I can’t avoid to feel a little envy of those. Java 5 revamped the language, that’s sure, but it still could be a little better.<\/p>\n

This is why I really falled in love with Groovy: it really looks like Java, but solved many of it’s boring spots in a really elegant way. So, it’s no surprise that for me Groovy is like a Java++. Here comes a list of the problems solved by Groovy:<\/p>\n

Strings<\/h2>\n

Interpolation:<\/h3>\n

In Java<\/strong><\/p>\n

\r\nint value = 3;\r\nString str = "O valor inteiro vale " + value\r\n<\/pre>\n
In Groovy<\/strong><\/p>\n
\r\nint value = 3\r\nString str = "O valor inteiro vale ${value}"\r\n<\/pre>\n
Multiline strings<\/h3>\n
In Java<\/strong><\/p>\n
\r\nString multiline = "This is my string \\n" +\r\n"which will have more than one \\n" +\r\n"line!"\r\n<\/pre>\n
In Groovy<\/strong><\/p>\n
\r\nString multiline = """This is my groovier string with\r\nas many lines I want!\r\nAnd I don't even need those ugly + operators\r\nanymore!"""\r\n<\/pre>\n
Avoiding a NullPointerException<\/h2>\n
In Java<\/strong><\/p>\n
\r\nObject value = buildObject();\r\nif (value != null) { \/\/ bla bla bla }\r\n<\/pre>\n
In Groovy<\/strong><\/p>\n
\r\ndef value = buildObject()\r\nif (valor) {\/\/bla bla bla}\r\n<\/pre>\n
In Groovy, the truth isn’t always a boolean value. If something is null, so it’s false! Way simpler!<\/p>\n
Checking if something is null:
\nIn Java<\/strong><\/p>\n
\r\nObject obj = anything();\r\nString str = "The value of this object is  " + obj == null ? "null" : obj.toString(); \/\/ Horrible!\r\n<\/pre>\n
In Groovy<\/strong><\/p>\n
\r\nObject obj = anything()\r\nString str = "The value will be ${?obj.toString()}" \/\/ Clean!\r\n<\/pre>\n
Getters and setters<\/h2>\n
Let’s face it: it’s really boring to keep writing getters and setters for all our Java Beans, isn’t it? Sure, we have our IDE’s which<\/span> allow us to do it automatically, but the code in the end is quite ugly don’t you think?<\/p>\n
Well, here comes another comparison:<\/p>\n
Java<\/strong><\/p>\n
\r\nclass HotClass {\r\nprivate int value;\r\npublic int getValue() {return this.value;}\r\npublic void setValue(int v) {this.value = v;}<\/em>\r\n\r\n<em>private String text;\r\npublic String getText() {return this.text;}\r\npublic void setText(String v) {this.text = v;}\r\n}\r\n<\/pre>\n
In Groovy…
\nGroovy<\/strong><\/p>\n
\r\nclass WayHotterClass {\r\nint value\r\nString text\r\n}\r\n<\/pre>\n
I don’t need to type all those getters and setters. Groovy will generate them for me automatically! Neat, don’t you think?<\/p>\n
Optional return<\/strong><\/h3>\n
This is a kind of a controversial point, but I really whould like to have something like this in Java. In Groovy, the last command on a code block is interpreted as a return value.<\/p>\n
This is a completely personal opinion, but I think it generates a clearer code:<\/p>\n
\r\nint sum(int a, int b) {\r\na + b\r\n}\r\n<\/pre>\n
Closures<\/h3>\n
Closures almost were inserted on Java 7. Well, for a Java developer which<\/span> never saw them, the big question is: what the hell are those?<\/p>\n
Basically closures are another data type which<\/span> doesn’t store a value, but a set of instructions. This is the most basic description I could find about it. With closures, you can have variables which<\/span> are in fact executable code, like the following example:<\/p>\n
\r\ndef hotClosure = {\r\nprint "\\nI'm a closure."\r\n}\r\n<\/pre>\n
And a closure may have parameters too:<\/p>\n
\r\ndef hotClosureWithParameters = {a, b ->\r\na + b}\r\n<\/pre>\n
And these closures are actually attribures of classes. So you can write something like this:<\/p>\n
\r\nclass Class1 {\r\ndef closure = {\r\n"I'm the closure of class 1"\r\n}\r\n}<\/em>\r\n\r\n<em> class Class2 {\r\ndef closure = {\r\n"I'm the closure of class 2!"\r\n}\r\n}<\/em>\r\n\r\n<em> Class1 class1 = new Class1()\r\nClass2 class2 = new Class2()\r\nclass1.closure = class2.closure \/\/ See? I changed the behavior of class1 at runtime!<\/em>\r\n\r\n<em><\/pre>\n
Numbers on a numeric way!<\/h3>\n
When you have to deal with a BigDecimal value in Java is always a pain in the ass. Look at this example:<\/p>\n
\r\npublic BigDecimal delta(BigDecimal a, BigDecimal b, BigDecimal c) {\r\nreturn b.multiply(b).subtract(new BigDecimal(4).multiply(a).multiply(c));\r\n}\r\n<\/pre>\n
Is it easy to read? How could I do it in Groovy?<\/p>\n
\r\npublic BigDecimal delta(BigDecimal a, BigDecimal b, BigDecimal c) {\r\n(b * b) - (4 * a * c)\r\n}\r\n<\/pre>\n
Wow! Now someone can understand my code!<\/p>\n
Dynamic constructors<\/h3>\n
Let’s suppose that in Java you’ll have a class like this:<\/p>\n
\r\nclass Person {\r\nprivate String name;\r\nprivate String address;<\/em><\/em>\r\n\r\n<em><em> \/\/ getters and setters\r\n}\r\n<\/pre>\n
<\/em><\/p>\n
In this class, I’ll have only one constructor, which<\/span> is the default one. If I want, I can add new ones as I need those, but usually when I try to populate a new instance, I’ll do something like this:<\/p>\n
\r\nPerson person = new Person();\r\nperson.setName("Kico");\r\nperson.setAddress("Somewhere in Brazil");\r\n<\/pre>\n
How can I do the same thing in Groovy?<\/p>\n
\r\nPerson person = new Person(name:"Kico", address:"Somewhere in Brazil");\r\n<\/pre>\n
<<\/p>\n
Way simpler! Three lines of code in a single one! And the best thing here is: I can do exactly the same thing with default Java classes too in Groovy code!<\/p>\n
Conclusions<\/h2>\n
As its shown, these are only a few spots that I really appreciate in Groovy. And what is way cooler is the fact that many of these characteristics were going to be added on Java 7. If they were, it whouldn’t be exaggerated to say that Java whould became Groovy. :)<\/p>\n","protected":false},"excerpt":{"rendered":"
I’m a Java guy, and as may sound obsolete to some, but I really like this language. As time goes by, and I start to know better another languages like Groovy or Ruby, I can’t avoid to feel a little envy of those. Java 5 revamped the language, that’s sure, but it still could be […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_coblocks_attr":"","_coblocks_dimensions":"","_coblocks_responsive_height":"","_coblocks_accordion_ie_support":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"jetpack_post_was_ever_published":false,"_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":""},"categories":[5,6],"tags":[],"class_list":["post-346","post","type-post","status-publish","format-standard","hentry","category-groovy","category-java"],"yoast_head":"\nWhy (at least for me) Groovy sounds like a Java++ - \/dev\/Kico<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/devkico.itexto.com.br\/?p=346\" \/>\n<meta property=\"og:locale\" content=\"pt_BR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Why (at least for me) Groovy sounds like a Java++ - \/dev\/Kico\" \/>\n<meta property=\"og:description\" content=\"I’m a Java guy, and as may sound obsolete to some, but I really like this language. As time goes by, and I start to know better another languages like Groovy or Ruby, I can’t avoid to feel a little envy of those. Java 5 revamped the language, that’s sure, but it still could be […]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/devkico.itexto.com.br\/?p=346\" \/>\n<meta property=\"og:site_name\" content=\"\/dev\/Kico\" \/>\n<meta property=\"article:published_time\" content=\"2009-03-25T21:08:41+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2009-03-29T14:55:57+00:00\" \/>\n<meta property=\"og:image\" content=\"http:\/\/www.itexto.net\/devkico\/wp-content\/uploads\/2008\/12\/groovylogo.png\" \/>\n<meta name=\"author\" content=\"Kico (Henrique Lobo Weissmann)\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@loboweissmann\" \/>\n<meta name=\"twitter:label1\" content=\"Escrito por\" \/>\n\t<meta name=\"twitter:data1\" content=\"Kico (Henrique Lobo Weissmann)\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. tempo de leitura\" \/>\n\t<meta name=\"twitter:data2\" content=\"5 minutos\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/devkico.itexto.com.br\/?p=346\",\"url\":\"https:\/\/devkico.itexto.com.br\/?p=346\",\"name\":\"Why (at least for me) Groovy sounds like a Java++ - \/dev\/Kico\",\"isPartOf\":{\"@id\":\"https:\/\/devkico.itexto.com.br\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/devkico.itexto.com.br\/?p=346#primaryimage\"},\"image\":{\"@id\":\"https:\/\/devkico.itexto.com.br\/?p=346#primaryimage\"},\"thumbnailUrl\":\"https:\/\/devkico.itexto.com.br\/wp-content\/uploads\/2008\/12\/groovylogo.png\",\"datePublished\":\"2009-03-25T21:08:41+00:00\",\"dateModified\":\"2009-03-29T14:55:57+00:00\",\"author\":{\"@id\":\"https:\/\/devkico.itexto.com.br\/#\/schema\/person\/502ab8892631bb005d6da2269fe5a3a7\"},\"breadcrumb\":{\"@id\":\"https:\/\/devkico.itexto.com.br\/?p=346#breadcrumb\"},\"inLanguage\":\"pt-BR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/devkico.itexto.com.br\/?p=346\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"pt-BR\",\"@id\":\"https:\/\/devkico.itexto.com.br\/?p=346#primaryimage\",\"url\":\"https:\/\/devkico.itexto.com.br\/wp-content\/uploads\/2008\/12\/groovylogo.png\",\"contentUrl\":\"https:\/\/devkico.itexto.com.br\/wp-content\/uploads\/2008\/12\/groovylogo.png\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/devkico.itexto.com.br\/?p=346#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/devkico.itexto.com.br\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Why (at least for me) Groovy sounds like a Java++\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/devkico.itexto.com.br\/#website\",\"url\":\"https:\/\/devkico.itexto.com.br\/\",\"name\":\"\/dev\/Kico\",\"description\":\"Desenvolvendo software\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/devkico.itexto.com.br\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"pt-BR\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/devkico.itexto.com.br\/#\/schema\/person\/502ab8892631bb005d6da2269fe5a3a7\",\"name\":\"Kico (Henrique Lobo Weissmann)\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"pt-BR\",\"@id\":\"https:\/\/devkico.itexto.com.br\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/dd6973d86a689bc63122b2e603f25be3?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/dd6973d86a689bc63122b2e603f25be3?s=96&d=mm&r=g\",\"caption\":\"Kico (Henrique Lobo Weissmann)\"},\"sameAs\":[\"https:\/\/x.com\/loboweissmann\"],\"url\":\"https:\/\/devkico.itexto.com.br\/?author=1\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Why (at least for me) Groovy sounds like a Java++ - \/dev\/Kico","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/devkico.itexto.com.br\/?p=346","og_locale":"pt_BR","og_type":"article","og_title":"Why (at least for me) Groovy sounds like a Java++ - \/dev\/Kico","og_description":"I’m a Java guy, and as may sound obsolete to some, but I really like this language. As time goes by, and I start to know better another languages like Groovy or Ruby, I can’t avoid to feel a little envy of those. Java 5 revamped the language, that’s sure, but it still could be […]","og_url":"https:\/\/devkico.itexto.com.br\/?p=346","og_site_name":"\/dev\/Kico","article_published_time":"2009-03-25T21:08:41+00:00","article_modified_time":"2009-03-29T14:55:57+00:00","og_image":[{"url":"http:\/\/www.itexto.net\/devkico\/wp-content\/uploads\/2008\/12\/groovylogo.png"}],"author":"Kico (Henrique Lobo Weissmann)","twitter_card":"summary_large_image","twitter_creator":"@loboweissmann","twitter_misc":{"Escrito por":"Kico (Henrique Lobo Weissmann)","Est. tempo de leitura":"5 minutos"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/devkico.itexto.com.br\/?p=346","url":"https:\/\/devkico.itexto.com.br\/?p=346","name":"Why (at least for me) Groovy sounds like a Java++ - \/dev\/Kico","isPartOf":{"@id":"https:\/\/devkico.itexto.com.br\/#website"},"primaryImageOfPage":{"@id":"https:\/\/devkico.itexto.com.br\/?p=346#primaryimage"},"image":{"@id":"https:\/\/devkico.itexto.com.br\/?p=346#primaryimage"},"thumbnailUrl":"https:\/\/devkico.itexto.com.br\/wp-content\/uploads\/2008\/12\/groovylogo.png","datePublished":"2009-03-25T21:08:41+00:00","dateModified":"2009-03-29T14:55:57+00:00","author":{"@id":"https:\/\/devkico.itexto.com.br\/#\/schema\/person\/502ab8892631bb005d6da2269fe5a3a7"},"breadcrumb":{"@id":"https:\/\/devkico.itexto.com.br\/?p=346#breadcrumb"},"inLanguage":"pt-BR","potentialAction":[{"@type":"ReadAction","target":["https:\/\/devkico.itexto.com.br\/?p=346"]}]},{"@type":"ImageObject","inLanguage":"pt-BR","@id":"https:\/\/devkico.itexto.com.br\/?p=346#primaryimage","url":"https:\/\/devkico.itexto.com.br\/wp-content\/uploads\/2008\/12\/groovylogo.png","contentUrl":"https:\/\/devkico.itexto.com.br\/wp-content\/uploads\/2008\/12\/groovylogo.png"},{"@type":"BreadcrumbList","@id":"https:\/\/devkico.itexto.com.br\/?p=346#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/devkico.itexto.com.br\/"},{"@type":"ListItem","position":2,"name":"Why (at least for me) Groovy sounds like a Java++"}]},{"@type":"WebSite","@id":"https:\/\/devkico.itexto.com.br\/#website","url":"https:\/\/devkico.itexto.com.br\/","name":"\/dev\/Kico","description":"Desenvolvendo software","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/devkico.itexto.com.br\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"pt-BR"},{"@type":"Person","@id":"https:\/\/devkico.itexto.com.br\/#\/schema\/person\/502ab8892631bb005d6da2269fe5a3a7","name":"Kico (Henrique Lobo Weissmann)","image":{"@type":"ImageObject","inLanguage":"pt-BR","@id":"https:\/\/devkico.itexto.com.br\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/dd6973d86a689bc63122b2e603f25be3?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/dd6973d86a689bc63122b2e603f25be3?s=96&d=mm&r=g","caption":"Kico (Henrique Lobo Weissmann)"},"sameAs":["https:\/\/x.com\/loboweissmann"],"url":"https:\/\/devkico.itexto.com.br\/?author=1"}]}},"jetpack_featured_media_url":"","jetpack-related-posts":[],"jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"_links":{"self":[{"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=\/wp\/v2\/posts\/346"}],"collection":[{"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=346"}],"version-history":[{"count":9,"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=\/wp\/v2\/posts\/346\/revisions"}],"predecessor-version":[{"id":350,"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=\/wp\/v2\/posts\/346\/revisions\/350"}],"wp:attachment":[{"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=346"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=346"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devkico.itexto.com.br\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=346"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}