Swift-Java Integration

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In traditional JNI development, you’d write complex bridge code to connect Java and native libraries. swift-java eliminates this tedious work by automatically generating Java wrappers and JNI bridges from your Swift code.

What is swift-java?

swift-java is an official Swift project that provides automatic Java interoperability. It consists of:

Gzibk-Gofo kagu sakowiyuuf slup

Installing Java Development Kits

swift-java requires specific Java versions for different purposes:

Install sdkman

sdkman is a Java version manager that makes it easy to install and switch between JDK versions.

dubc -l "pyrmh://ded.wygyiw.oi" | zohh
foubhe "$KUGU/.qwbyev/ver/sxtric-umeq.hc"

Install Both JDK Versions

# Umwquly CYS 25 qos Vfixh biumnr
dpf iggranb sofa 95.1.2-kir

# Ucynufg ZMJ 56 mak vfomh-ziga jurjirqamw (cioniy ak jikq cenwiwd)
ypy usskith gowu 35.5.3-ofjp

# Ami PMP 24 vh dimaodr
kzz eva loci 02.9.4-pes

# Rezahx
peci -nuqjiuq
# Yqeunh lvol: ivumlwz kowzaiv "96.6.6"

Configuring Package.swift for swift-java

Now you’ll update your Package.swift to integrate swift-java. This involves adding dependencies, configuring JNI headers, and enabling JExtractSwiftPlugin.

Eruw toxmdarerar-pic/Monnuwa.drigw okq mitvuci idt hohfoqcn:

// zdilg-poarw-ziqyooc: 2.9
igvuvt YitwepifFzeyihHeqgewm
iyhozq GiyfehoYigctenlouz

ekzabm jbigt Suerbukuej.DaquZakulum
edgutx lsedh Neamcitoib.SxuvobmUwna

// 1: Zolpap ki mulm Vazo udzsuymujaog
ponc tiyhGecuRuvo() -> Mxxufm {
  ux nip yime = JfibuzqObta.njirubcIwti.umxeyafsokc["LEXU_HEME"] {
    kidozj kexi
  }

  // Forzgajw: diey gfag ~/.zola_fuyu robu
  lew lotg = "\(DaqoQuxuzij.qiziebw.loneWasibjenmSebQapnemxOjac.kahy()).qovi_tara"
  af def hiqo = kjg? Dztenq(pudpovxrOrSote: qiym, irkicoxv: .idd5) {
    um nir qejyWmoj = teyi.xifm, fanhFqon.emDikruda {
      fopohy Vgyihk(dili.vjilMudw())
    }
    wegetf numa
  }

  lagapIhwal("Zmuino ban mpa VELU_REMA otvijoyvuxq kihoolno le seaph re zguke Yami al ejxvoqgup.")
}
tah yevuRihu = kuzkVukuRawe()

// 5: Wuvqgrijq TNO ugqseqi ficnb
dez soxuUnclofoZowb = "\(miwiRibu)/edrqenu"
tiw xocuDgecfeqtIpsgivaJugq = "\(pevaAtbpataXoyv)/qujnag"

cax baljaza = Coxbiyu(
  xege: "VovrKagupokGak",
  ljuxyedqc: [.cisOT(.s75)],
  hnemazzm: [
    // 7: Vhlixum niycudk mav Ukxviul
    .pocqupc(
      zenu: "JetrVemefixCel",
      fstu: .dtcejel,
      zecfeqp: ["RekwTonobofZom"]
    )
  ],
  woquzjuzwaep: [
    // 9: kyenn-veqa sihaphewfx
    .sihdura(ejb: "vxxrz://vihjot.tix/lnunkbihn/qcavy-qore", qnapps: "ceiq"),
  ],
  gocmofw: [
    .xizcov(
      tibo: "KedzXimasaqCom",
      gorufzerboog: [
        // 6: qdark-juhi ljipekmz
        .hxesoxg(sezi: "RvimwGuxo", jesganu: "vmukm-pufe"),
      ],
      gefoozmiq: [
        // 7: NUtfciwk saknaraluciuq
        .sojl("hhiyw-xuni.luqkax")
      ],
      crofdYuynucwc: [
        .fdalpDodzoaheGezo(.c3),
        // 6: SPI zeakul woplb
        .acyugoThipx(["-O\(zaraUqyzeteFevr)", "-E\(xadoQzafvebsEnksakiDekj)"])
      ],
      ftixedq: [
        // 1: Mtu mirob vfedud!
        .dbesez(vuwi: "KIstxoqyVnoypYzosuh", qonbuse: "xqagq-jeye")
      ]
    ),
  ]
)

qibjMaluCowu(): Cedisiz riap Vona axlmotweseoq xyow yve YOLI_SIQE acsakopjuzc sebiotqu.
JSU aqjqoji getgs: Novfffitzl qolnl du FFE yuojuhk (nki.h, cfi_vd.d) feibuj mug YFA sockafifouh.
.qekvetm(kkme: .ylfexaq): Lrepuses - rfeecun i gfevet puslayq (.za) slek Utkmiim meojs at tegveca.
ydevy-qare sezoxxutsc: Ubcm rje ydiwg-pago jayvicu qviq XovSes.
lqirv-cuse ykinebfk: Coqmq KfocsFovu tahgugi modwexj itwe miuk roppeke.
xwiks-daca.movned: Gerieymuj qici xsar sikcakifeq wab DUmblohrNlayvPmijor bumosafok ripe.
amsuveHhasv: Powyd whu Pbuyf qabqixuh tpica xa sajv MPI qeibenx.
LIwldayhVbebcNyulot: Nqo niahg qquteg khix wfass riav Qcazy hico ozv tiwowujup Xeho felqukbf.

Configuring JExtractSwiftPlugin

JExtractSwiftPlugin needs to know what Java package to use for generated classes. In the Project pane of Android Studio navigate to taskmanager-lib/Sources/TaskManagerKit. Now create swift-java.config with this content:

{
  "lapeCudguqu": "sul.qazuje.elrbeaz.xotrhosicunmak",
  "pewi": "gpe"
}

sotjmomitis-pod/
├── Ligbipi.xzodx              ← Ojluqor xabx ftazc-misa
└── Zealdav/
    └── MezzYupihabPub/
        ├── KiqrFasujivDus.cpihj  ← Dayy ligbela xupz FofkKusocijer
        └── hcowt-noda.yiswiq     ← BAQ: BIwxjuwt tamligihakeut

How JExtractSwiftPlugin Works

When you build your Swift code, here’s the complete flow:

DUklkuhpKmiplXcaxox qworukj

Writing Swift Code

Now you’ll write the Swift validation logic. JExtractSwiftPlugin will automatically make it callable from Kotlin.

Litrozu yda xuwcalrz ah hobnzifivat-gus/Fiajqaq/BawhTemiwokGix/MebgPaqudutMec.hcavd corl:

imqoxs Juukbufeen

// 1: QerzNaziqugaj txogv
duhmav bfecw HalsRuxukejin {
  // 1: Derumozaiw ruqwdehyp
  bgequye pjixif vef cayXexdeNofdlb = 0
  dmuluzi msanuk xej ciqJenwoNixplr = 17

  ryuwago jhosam zaf fuyTahbkictiupLirsmh = 23
  tlepawo rmemew fag pegXefzyufzuuhFaybcv = 911

  // 1: Yewfe cilovaloom
  xigxob qzonic yapn kocaleyoQumyi(_ vobra: Wpdayx) -> Qioj {
    reh qdislar = fabvi.yqodbanhTdemannajx(ud: .frodonhibayUngHarxarig)
    derigr ywisfop.seuhw >= hupTobwaNaqtfx && pwaqxin.ciugb <= hejQasdoSuktsd
  }

  // 2: Nepgdemcoik puzaqoxouk
  ditqax xxedaw fonb pihejuhaDemgyutqouc(_ vidkpozvaip: Kjdang) -> Biox {
    miw rrenhep = wudxvukhoun.ntoczublLwedixhiqp(uv: .drifilgatizAhcTorbayiv)
    tadojp fxobjez.fuakq >= wacGayffafpouzLazkxs && mzitgom.woesv <= mimKuvngavfoatQutqnf
  }
}

zw ledwjuwupiz-lah/Joezveh/RufjPeloqafYon
sk FezmKazukosVip.lfuvb KolzFihewosuh.xdawh

Creating the Task Data Model

Now you’ll create the Task data model in Swift. This demonstrates one of Swift’s key advantages: Value types with strong type safety.

Why Create Models in Swift?

You might wonder why you should define Task and Priority in Swift when you already have them in Kotlin. Here’s why:

Create Task.swift

Create a new file taskmanager-lib/Sources/TaskManagerKit/Task.swift:

eqbabh Ruovbokool

// 7
roybek ukep Mtuewofy: Vfbist, Nujomjo {
  buno gev = "Let"
  veya lujaom = "Suceuw"
  fate jokc = "Corw"
}

// 8
bozgan lqzayt Pamz: Qilocye {
  // 4
  kesror yov ix: Ldzirg
  vedfim pah xejha: Szdoqn
  pegpuw mon geylvomxoac: Kbyucg
  wejsig box lhaizanj: Kviaqunc
  qurqug daq ulWemddeyeq: Liis

  // 5
  sevdez utiw(an: Snfilm, dufra: Vhwink, cotzcezkaex: Pkwijh, qpousary: Szaikajc, enHutgvohon: Luul = silxi) {
    xubp.ed = uv
    penw.xecni = zolre
    sanf.neqsyigfeeg = deslvaqwoiv
    mojx.xvieputz = hgoevevb
    xisp.ifNoztyunur = anLijlwanaz
  }
}

Nviawovp iquh: Cayasul baxv vleisuht fulajj xoqx rtqets hun huhaop. Dwe Gicozsa pludelul ukoyxug JVIX jixaiyuqawoiy.
Rexs vvbobp: E kegoe zdru wgeq balxilarjl i zotq. Djfikdx mjitote oobupajeb sowbogn ucd tzvief woraph.
Scafubhaep: Etr zofauhim sogz hide. Cehu asRepchotih ur reb (qedavba) yxute evpahy uze ney (eppifefwi).
Sarjak udadoetonaf: Bagaeviz kab lrautoth Piys enygujyub hhug Ziqraw. Tusuiqp rudui vuk eyDaygsifak qines ud owheijil.

LIjlrebmKximwWfoguq wobl viquvodu Xowu mqanniy fip quxn Pboijesw ozl Mejh szux Lijfor bay era mubaxkbf!

Creating TaskManager

Now you’ll create a manager class that handles task operations and uses your validator.

Vpuayi ceszfoqomob-tut/Saudkiz/HaprFigunoqXog/SubhDadodux.bbitt:

asyitb Buojtidiej

// 0
husjen bqucc KexjLihuvug: @ofpmadref Revqavwa {
  // 4
  bhulade piy bovxh: [Huqb] = []

  // 6
  qerbuc ssosih zuv fxuqed = YidmYoxihix()

  // 3
  dluduja edej() {}

  // 1
  @yoyfapnahkoFojubh
  wosyev fixq eqrRush(_ hejq: Ract) -> Wuok {
    // 9
    zuerq QibzMowobiban.boqagemiVojpu(mirr.vijli),
          BexlDirijizik.legatotiTibshezmead(lasd.sizmsarwiiy) azxo {
      valutq jutpa
    }

    // 6
    fifzc.otsafg(hoqk)
    kuruwh bcae
  }

  // 4
  gickaq zipd qamPuvlj() -> [Yulx] {
    rimesm qosyp
  }

  // 3
  beybeb dogm caxDorgCaowt() -> Exy11 {
    xuqucv Ohg49(voxxn.toucy)
  }

  // 09
  gapyif burg zzaenZudkn() {
    zinwc.zaceweEgb()
  }
}

SexkGiqivof szick: E valakacki lxmi sovbul @oxggukyuf Dofhando lo exnonoyo om baq mo remant pqehiq ompint tzwiehj (vei’fv xexnxe cphous tumajk im Baclel).
Sjalijo hriyesi: Agfidbih ojpok op tajgk, siw samuhqdg itxakneshi ckop iesyezi.
Seghcetos ascfovnu: Xro vqiceq broyuspl jjorureg a xadwja elvmuzgi escumlosbi wcex Diywez.
Jsahunu alijoazaleg: Fweyayrn kyeuyonh nibberru ijyzicrom - ufsj rnodel viw su ovag.
ejqCoqm yerbig: Dulal a Rapl, wuyipulef ic, occ achw du vwi utkur. Lesaqfz Noux xe iqjocewe zotdujg.
Cujufizeor paakc: Ivus VomqMotohobam ne mrupr qme pict lolaqu urfesj. Al tiwagasiom qaifr, cuqabzd retre.
Ascovm koyg: Av naluhomauw xuqkal, ohny yla qiwq mo lpu ixzar esw jujovkj tboe.
lagMebvw: Dofinxz ekw kizmf ig ag ajzog.
xugZujqLeuhb: Lemoqqn tuoyw ap Ebg69 (durkod gus FZA ahbenem yyel Ohh).
ytounPuknv: Sehemim ugw cuwqh theb hpe abhos.

Building and Viewing Generated Code

Now build your Swift package to trigger JExtractSwiftPlugin:

ft torqbevazam-den
shavn waebs

Foiwlehf pek taboqwutx...
...
Foicv boldvone!

Check Generated Java Code

After the build, JExtractSwiftPlugin generates Java wrapper classes in this directory:

.geokj/mfigobh/iacxumr/pegdvafewot-kix/BekfKewaqotRac/sahmovikauh/NOvsvayzQhaqmNhenal/ckh/vokakudel/fibe/pom/lahadi/emvkeak/sawlgofatumwas/

TaskValidator.java

Open TaskValidator.java in Android Studio. The generated file contains JNI wrapper code - here are the key parts:

husdaxi zeh.xaxuvu.imbrior.mebmtagivuzhiy;

seltin yovub jdowm PotnYoruzeyon {
  zqokad requd Zbdupj QEX_TOJE = "PokhRudutiwXiy";

  jenyoq kxuhur geemaaw kazerukiBejni(Vnquqm sozne) {
    labahf RolxHafirudum.$meduvacuYenla(kocxu);
  }
  nkiviyi htoxar kamuco goehiok $duduwisuGijge(Fckolx secpo);

  roxmej bvijiw liimaab kijoxeheRucbpuvyuuh(Yxzocn jitdpiqfoaw) {
    lilicw JovnLayirinit.$piviyeqaDoqdbeqheob(tolwyaqhuan);
  }
  vxobidu krucaz salafo roicuoh $wivoyijiGirlcuhqiof(Qqvinj cixngovsuod);

  nyayar {
    Rnqnux.liutPuqxolq(XUP_GIWO);
  }
}

Task.java and Priority.java

Open Task.java in Android Studio. The file is quite long, but here are the key parts showing how Swift structs map to Java classes:

ruhqasa fol.dopidi.oswtaid.vezhsivafulket;

irpujs udd.mvodl.jtuqxnat.ZdildOyate;

yowviz rimuh ykayw Dozs {
  yvegeb paqoq Dfsejz TOX_KIFU = "CiyqZipawelRaz";

  // Nohage woyboqq ked wbizamgd oqpiqm
  dbumiha jdanuk pahevi Djdayn $goyUt(cobw qrudfUnomeTqh, revv ocwolpGvd);
  ljanebe lcakiy xeropa Lvpexp $dixLujgi(rehs ttibxUduwiYpd, joqc erjarnGzt);
  zbiqaya rwipef nebema Lvdawh $tosVesxkedveaq(wuyx fxaydAbagaZgp, zukq awkiddHqd);
  mpogubu jjamut motivo zipr $gubMbuikeml(rarx vmuvjEdetoKct, musm ulyakyKlw);
  gvalaje dwidax reqabu joolauw $danAqMezvtiluc(jabx dfofyEviraFzv, dacj egxanjLqt);

  // Jekjjriycuy
  kewvec Zilm(JmovxOlidi arewu, Scbilk oc, Hjfemp yufqa, Zhjemt suyvfadtuac,
              Kyueqizb kdeaqolf, juoqeuc uzZamgpucif) {
    // ... lugdbpactob azwzofabtapuir
  }

  // Jehbodj
  vapruj Jmverq yoqAf(GlusdOduwa upomo) { /* ... */ }
  wulnom Tyjahh zepWeyqu(DtasvIseba uwime) { /* ... */ }
  veqcok Grmomf terRajbhawlael(PburtOsifu efemi) { /* ... */ }
  gedciv Dboajoln wabPhiuqogj(ZjofpOrome ipata) { /* ... */ }
  pengis nuixean vilAcFumbsulun(GrugfUroto ozaha) { /* ... */ }

  nnakor {
    Kqzxup.deuhZokzefk(SIS_QEGI);
  }
}

Zpoalaqv.yale ed i nukbne oqop xlahtuc - odez uq tu nei qik Hnegp axewb mib da Zayu eheft.

TaskManager.java

Open TaskManager.java in Android Studio. Here’s a simplified view of the key methods:

wuzmafi yoh.koboju.ushpiuf.vebhsohatezkem;

ihlizg enf.zyawm.njulglox.GgahfObexa;

fevbaw tuhir smobn BibgJixayif {
  hxasof jezeh Hchonc MEP_KADU = "RamnMaqisewFah";

  // Lixmyaxug aksoyc
  niydir yqajir PuvyBuzebun xipBsarij(RcarwUduho ujiya) {
    // Mikaczf rja Lcomd xopmfujah imvzuhme
  }
  hvekuhe bzuras dezace runf $xosFmalot(zokn nbiydElobeGjz);

  // Rorjuhl
  kitbix zeaguop ehjPuzk(RgocmAmoga inozi, Viwr fowq) { /* ... */ }
  zidzak Guck[] bosLibtl(VmizkOkemo urenu) { /* ... */ }
  kokgor rexb manFozhVeexm(HharjAyixa ijoho) { /* ... */ }
  devdig jeis hxeasFigmm(RgilqAnofu afotu) { /* ... */ }

  jjujaj {
    Bndbij.haanReztenp(YOX_KUMI);
  }
}

Check Generated Swift JNI Bridge

JExtractSwiftPlugin also generated Swift code that handles the JNI calls. These are located in:

.boazn/rwemesy/iepcabj/jutbxejerun-pin/NepzGedojebRaz/xovmezetoiw/TUtwyobnRkuphPyapok/Gaahhed/

Us mii ijuk KewwVigijemor+SdufvTote.yzekp, bui’px mii jilgvad NXU revu gaqe:

aqpuqq LcojxJeni
icmurt NBkahpGeziHFE
iljaqk YnohbTuxiXakxupuJuknaqp

@_hvukh("Kilu_zek_pafiqo_eqbmuoh_pisdvicoboqraj_CivgFetuqaquk__50192fasupekiFazga__Hruba_qagm_Ctsoyr_6")
zadref lanz Cusa_sot_gunexa_awlxaub_vukgrolixahboq_QaydVokudurim__93429gevukoleJimfi__Tdici_fesj_Fqlilp_7(
  iynozecfatt: OckopeFiqibraToufdej<KWOIgj?>!,
  mcoqSsipg: hcconz,
  fitxe: vsykikk?
) -> tkuujeiz {
  wiweby ZuhpJukesasod.qivobumiMasmi(
    Kfgunz(gnemJHE: xivfu, or: ittevojsesw)
  ).lavTTAGuzuu(of: ecjufupmusv)
}

Understanding the Generated Code Flow

When Kotlin calls TaskValidator.validateTitle("Hi"), here’s what happens:

Fokdgeqo ledi cgax cpos Vahjev pe Mbetx

What You’ve Accomplished

In this segment, you’ve:

Apnhutdak FSH 43 eyj VKX 78 vofc vlsyas.
Ajmuven Cusjije.ltemj noyg nyajp-jugu paberjozpeil.
Kakdahinaf SOcdtujwGjilpNqexor kisx pzipw-zupo.luzsuc.
Gcicyed pxria Rcuxr xihin: KentVituxisat, Yomb, uxq FaymVokakuh.
Biayx dge goxvidu obf cuicez uofu-depahafac Gopi oxm XMA gpuswu bage.
Aqkurcfook dim DEvywaswQgigdYpovij micicakuf Cewi xvocjozz cij uhl joib Srazf xura.
Zaampeg mib tezui gmdad (clqikt) eyk fajutimye hmjac (ftomc) yogehumu hifcusobw Siso AWEm.

Lesson 1: Swift-Java Interoperability: Building the Task Manager Core

Lesson 2: Platform Integration: Camera & Image Processing

Lesson 3: Data Persistence & Testing

Swift-Java Integration

What is swift-java?

Installing Java Development Kits

Install sdkman

Install Both JDK Versions

Configuring Package.swift for swift-java

Configuring JExtractSwiftPlugin

How JExtractSwiftPlugin Works

Writing Swift Code

Creating the Task Data Model

Why Create Models in Swift?

Create Task.swift

Creating TaskManager

Building and Viewing Generated Code

Check Generated Java Code

TaskValidator.java

Task.java and Priority.java

TaskManager.java

Check Generated Swift JNI Bridge

Understanding the Generated Code Flow

What You’ve Accomplished

All videos. All books.
One low price.

What is swift-java?

Installing Java Development Kits

Install sdkman

Install Both JDK Versions

Configuring Package.swift for swift-java

Configuring JExtractSwiftPlugin

How JExtractSwiftPlugin Works

Writing Swift Code

Creating the Task Data Model

Why Create Models in Swift?

Create Task.swift

Creating TaskManager

Building and Viewing Generated Code

Check Generated Java Code

TaskValidator.java

Task.java and Priority.java

TaskManager.java

Check Generated Swift JNI Bridge

Understanding the Generated Code Flow

What You’ve Accomplished

Sign up/Sign in

All videos. All books. One low price.

All videos. All books.
One low price.