{"id":506,"date":"2011-08-20T15:28:00","date_gmt":"2011-08-20T15:28:00","guid":{"rendered":"http:\/\/www.javacodegeeks.com\/2012\/10\/web-services-in-ruby-python-and-java.html"},"modified":"2012-10-21T20:06:22","modified_gmt":"2012-10-21T20:06:22","slug":"web-services-ruby-python-java","status":"publish","type":"post","link":"https:\/\/www.javacodegeeks.com\/2011\/08\/web-services-ruby-python-java.html","title":{"rendered":"Web Services in Ruby, Python and Java"},"content":{"rendered":"
Today I\u2019ve had to prepare some examples to show that web services are interoperable. So I\u2019ve created a simple web service in Java using Metro and launched it on Tomcat.<\/p>\n

Then tried to consume them using Python and Ruby. Here\u2019s how it all finished\u2026<\/p>\n

Web service in Java<\/span><\/p>\n

I\u2019ve started with a simple web service in Java:<\/p>\n

package com.wordpress.jdevel.ws;\r\n\r\nimport java.io.File;\r\nimport java.io.FileFilter;\r\nimport java.io.FilenameFilter;\r\nimport java.util.ArrayList;\r\nimport java.util.List;\r\nimport javax.jws.WebService;\r\nimport javax.jws.WebMethod;\r\nimport javax.jws.WebParam;\r\n\r\n@WebService(serviceName = \"Music\")\r\npublic class Music {\r\n\r\n    private static final File FOLDER = new File(\"D:\/TEMP\/SONGS\");\r\n\r\n    @WebMethod(operationName = \"listSongs\")\r\n    public Song[] listSongs(@WebParam(name = \"artist\") String artist) {\r\n\r\n        List<Song> songs = new ArrayList<Song>();\r\n        System.out.println(\"ARTIST: \" + artist);\r\n        if (artist != null) {\r\n            File folder = new File(FOLDER, artist);\r\n            if (folder.exists() && folder.isDirectory()) {\r\n                File[] listFiles = folder.listFiles(new FilenameFilter() {\r\n\r\n                    public boolean accept(File dir, String name) {\r\n                        return name.toUpperCase().endsWith(\".MP3\");\r\n                    }\r\n                });\r\n\r\n                for (File file : listFiles) {\r\n                    String fileName = file.getName();\r\n                    String author = file.getParentFile().getName();\r\n                    int size = (int) (file.length() \/ 1048576); \/\/Megabytes\r\n                    Song song = new Song(fileName, author, size);\r\n                    songs.add(song);\r\n                }\r\n            }\r\n        }\r\n\r\n        return songs.toArray(new Song[songs.size()]);\r\n    }\r\n\r\n    @WebMethod(operationName = \"listArtists\")\r\n    public String[] listArtists() {\r\n        File[] folders = getFolders(FOLDER);\r\n        List<String> artists = new ArrayList<String>(folders.length);\r\n        for (File folder : folders) {\r\n            artists.add(folder.getName());\r\n        }\r\n        return artists.toArray(new String[artists.size()]);\r\n    }\r\n\r\n    private File[] getFolders(File parent) {\r\n        FileFilter filter = new FileFilter() {\r\n\r\n            public boolean accept(File pathname) {\r\n                return pathname.isDirectory();\r\n            }\r\n        };\r\n\r\n        File[] folders = parent.listFiles(filter);\r\n\r\n        return folders;\r\n    }\r\n\r\n    public static void main(String[] args) {\r\n        Music listFiles = new Music();\r\n        String[] artists = listFiles.listArtists();\r\n        System.out.println(\"Artists: \" + artists);\r\n        for (String artist : artists) {\r\n            Song[] listSongs = listFiles.listSongs(artist);\r\n            for (Song song : listSongs) {\r\n                System.out.println(song.getArtist() + \" : \" + song.getFileName() + \" : \" + song.getSize() + \"MB\");\r\n            }\r\n        }\r\n    }\r\n}\r\n<\/pre>\n
Needed also a simple bean to get some more complex types:<\/p>\n
package com.wordpress.jdevel.ws;\r\n\r\nimport java.io.Serializable;\r\n\r\npublic class Song implements Serializable {\r\n    String fileName;\r\n    String artist;\r\n    int size;\r\n\r\n    public Song() {\r\n    }\r\n\r\n    public Song(String fileName, String artist, int size) {\r\n        this.fileName = fileName;\r\n        this.artist = artist;\r\n        this.size = size;\r\n    }\r\n\r\n    public String getArtist() {\r\n        return artist;\r\n    }\r\n\r\n    public void setArtist(String artist) {\r\n        this.artist = artist;\r\n    }\r\n\r\n    public String getFileName() {\r\n        return fileName;\r\n    }\r\n\r\n    public void setFileName(String fileName) {\r\n        this.fileName = fileName;\r\n    }\r\n\r\n    public int getSize() {\r\n        return size;\r\n    }\r\n\r\n    public void setSize(int size) {\r\n        this.size = size;\r\n    }\r\n}\r\n<\/pre>\n
It\u2019s just listing all sub-directories in hardcoded FOLDER directory and treats it as list of artists in music collection. Then you can execute listSongs method and get list of mp3 files in artist sub-folder.
 
<\/div> <\/div><\/p>\n
To make it a web service all you have to do is annotate class with @WebService(serviceName = “Music”) and every method you want to expose as web service operation has to be marked with @WebMethod(operationName = “listArtists”).<\/p>\n
This should be all if you\u2019re deploying it on GlassFish, but I\u2019ve used Tomcat, so 3 more steps were needed:<\/p>\n
1. Add Metro 2.0 jars to WEB-INF\/lib
\n2. Add Metro servlet and listener to web.xml:<\/p>\n
<listener>\r\n\t<listener-class>\r\n\t\tcom.sun.xml.ws.transport.http.servlet.WSServletContextListener\r\n\t<\/listener-class>\r\n<\/listener>\r\n<servlet>\r\n\t<servlet-name>Music<\/servlet-name>\r\n\t<servlet-class>com.sun.xml.ws.transport.http.servlet.WSServlet<\/servlet-class>\r\n\t<load-on-startup>1<\/load-on-startup>\r\n<\/servlet>\r\n<servlet-mapping>\r\n\t<servlet-name>Music<\/servlet-name>\r\n\t<url-pattern>\/Music<\/url-pattern>\r\n<\/servlet-mapping>\r\n<\/pre>\n
You probably shouldn\u2019t change anything here. Just paste it to your web.xml in web-app node.<\/p>\n
3. Add sun-jaxws.xml file to WEB-INF with endpoint declaration:<\/p>\n
<?xml version=\"1.0\" encoding=\"UTF-8\"?>\r\n<endpoints version=\"2.0\" xmlns=\"http:\/\/java.sun.com\/xml\/ns\/jax-ws\/ri\/runtime\">\r\n\t<endpoint implementation=\"com.wordpress.jdevel.ws.Music\" name=\"Music\" url-pattern=\"\/Music\"\/>\r\n<\/endpoints>\r\n<\/pre>\n