Download e-booknya dimana? free engga? Sincerely, Martin
________________________________ From: Samuel Franklyn <[EMAIL PROTECTED]> To: jug-indonesia@yahoogroups.com Sent: Wednesday, 12 November, 2008 16:08:33 Subject: Re: [JUG-Indonesia] Tanya Singleton irfani YangBaikHati wrote: > baru tau saya. nice input pak. Kalau mau lebih detail bisa baca di Effective Java Second Edition nya Joshua Bloch. > > Arif Rachim wrote: >> http://en.wikipedia .org/wiki/ Singleton_ pattern#Java >> Di java 5 pattern diatas sudah masuk TONG SAMPAH !!! >> >> Untuk meng guarantee bahwa object di java di singleton adalah >> menggunakan ENUM !! sebab specifikasi jvm, bertanggung jawab bahwa >> hanya akan ada 1 instance java enum. >> >> Pattern singleton seperti dibawah ini : >> >> public class Elvis{ >> private Elvis(){} >> private static Elvis theKing; >> private String name = "KING ELVIS"; >> public static Elvis getInstance( ){ >> synchronized( Elvis.class) { >> if(theKing ==null) theKing = new Elvis(); >> return theKing; >> } >> } >> public void setName(String name){ >> this.name <http://this. name> = name; >> } >> public String getName(){ >> return name; >> } >> } >> >> sudah obsolate. Bisa kita replace dengan cara ini >> >> public enum Elvis{ >> THE_ONE("KING ELVIS"); >> private Stirng name; >> Elvis(String name){ >> this.name <http://this. name> = name; >> } >> public void setName(String name){ >> this.name <http://this. name> = name; >> } >> public String getName(){ >> return name; >> } >> } >> >> JVM akan meng-guarantee bahwa singleton ini bener2 singleton di >> aplikasi kita. Nah kalau mau buat jadi lazy load tinggal ikutin >> patternnya on demand holder jadi seperti ini : >> >> public enum King { >> ELVIS; >> public enum Elvis{ >> THE_ONE("King Elvis"); >> private String name; >> Elvis(String name){ >> this.name <http://this. name> = name; >> System.out.println( name); >> } >> } >> >> public static Elvis getElvis(){ >> return Elvis.THE_ONE; >> } >> } >
