I
UNIVERZA V LJUBLJANI
FAKULTETA ZA RAUNALNITVO IN INFORMATIKO
Rok Logonder
UPORABA ORODIJ ZA OBJEKTNO-RELACIJSKO
PRESLIKOVANJE PRI RAZVOJU JAVANSKIH
APLIKACIJ
DIPLOMSKO DELO
VISOKOOLSKI STROKOVNI TUDIJSKI PROGRAM PRVE STOPNJE
RAUNALNITVO IN INFORMATIKA
Mentor: vi. pred. dr. Damjan Vavpoti
Ljubljana, 2011
I
Zahvala
Zahvalil bi se rad svoji druini za omogoanje tudija ter podporo pri le-tem, svojim soolcem, ki so
mi olajali sam tudij na fakulteti ter vsem, ki so v asu tudija tako ali drugae vplivali name kot na
tudenta in kot na loveka, predvsem dekletu Jerneji.
Posebna zahvala gre mentorju, vi. pred. dr. Damjanu Vavpotiu, ki me je s hitrimi odzivi na moja
vpraanja, nasveti in predlogi vodil k dokonanju diplomske naloge.
Zahvaljujem, se tudi podjetju ZZI d.o.o. za vse, kar so mi v preteklih tirih letih omogoili.
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Kazalo vsebine
Povzetek ........................................................................................................................................................... 1
Abstract ............................................................................................................................................................ 2
1 Uvod ......................................................................................................................................................... 3
1.1 Cilj diplomske naloge ........................................................................................................................ 4
2 Opis teorije ............................................................................................................................................... 5
2.1 Osnovni pojmi ................................................................................................................................... 5
2.1.1 Relacijske podatkovne baze ...................................................................................................... 5
2.1.2 Java ........................................................................................................................................... 5
2.1.2.1 Objekt ................................................................................................................................... 5
2.1.3 Trajnost ..................................................................................................................................... 6
2.1.4 Refleksija................................................................................................................................... 6
2.1.5 Razirjanje ................................................................................................................................. 6
2.2 Objektnorelacijsko preslikovanje .................................................................................................... 7
2.2.1 Zakaj se uporablja objektnorelacijsko preslikovanje ............................................................... 7
2.2.2 Standardi .................................................................................................................................. 8
2.2.2.1 JDO........................................................................................................................................ 8
2.2.2.2 JPA ........................................................................................................................................ 9
2.2.3 Primer delovanja objektno-relacijsko preslikovalnih orodij, ki se drijo standardov JDO ali pa
JPA 9
3 Objektnorelacijski preslikovalniki ......................................................................................................... 10
3.1 Seznam in primerjava preslikovalnikov........................................................................................... 10
3.2 Rezultat primerjave ........................................................................................................................ 11
3.2.1 Kriterij tevilo vrstic kode in datotek ter as pri vzpostavitvi povezave s podatkovno bazo
11
3.2.2 Kriterij Enostavnost uporabe .............................................................................................. 12
3.2.3 Kriterij Hitrost delovanja enostavnih poizvedb ter poizvedbe primerljive s poizvedbami, kot
smo jih izvajali v podjetju ..................................................................................................................... 12
4 Objektnorelacijsko preslikovalna orodja .............................................................................................. 14
4.1 MyBatis ........................................................................................................................................... 14
4.1.1 Delovanje ................................................................................................................................ 14
4.1.1.1 XML nastavitvena datoteka ................................................................................................ 15
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4.1.1.2 Preslikovalna XML datoteka ................................................................................................ 17
4.1.1.3 Dinamini SQL ..................................................................................................................... 21
4.1.2 Prednosti in slabosti ............................................................................................................... 22
4.2 Hibernate ........................................................................................................................................ 23
4.2.1 Delovanje ................................................................................................................................ 23
4.2.1.1 Hibernate konfiguracijska datoteka .................................................................................... 23
4.2.1.2 Modelni razred ................................................................................................................... 24
4.2.1.3 Monosti ............................................................................................................................. 24
4.2.1.4 Crud operacije..................................................................................................................... 26
4.2.2 HQL ......................................................................................................................................... 27
4.2.2.1 Shranjevanje v predpomnilniku: ......................................................................................... 29
4.2.3 Prednosti in slabosti ............................................................................................................... 30
4.3 DataNucleus ................................................................................................................................... 31
4.3.1 Delovanje ................................................................................................................................ 31
4.3.2 Podprti podatkovni zbiri ......................................................................................................... 31
4.3.3 Tipi JDO objektov .................................................................................................................... 32
4.3.3.1 Podprti javanski tipi spremenljivk ....................................................................................... 32
4.3.3.2 Metadata nastavitve ........................................................................................................... 33
4.3.4 JDOHelper ............................................................................................................................... 33
4.3.5 Persistance manager Factory .................................................................................................. 34
4.3.6 Trajnostni urejevalnik ............................................................................................................. 34
4.3.7 Transakcija .............................................................................................................................. 34
4.3.8 Vraanje objektov ................................................................................................................... 34
4.3.9 JDOQL ..................................................................................................................................... 35
4.3.10 Prednosti in slabosti ............................................................................................................... 36
5 Zakljuek ................................................................................................................................................. 37
6 Viri .......................................................................................................................................................... 39
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Kazalo slik
Slika 1: Objektno-relacijsko preslikovanje.. ...................................................................................................... 7
Slika 2: Slikovna ponazoritev delovanja orodja MyBatis. ................................................................................ 14
Slika 3: primer XML nastavitvene datoteke. ................................................................................................... 15
