Video: Dab tsi yog chav kawm handler hauv Java?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
A tus tuav yog ib qho lus queue. Koj tshaj tawm cov lus rau nws, thiab nws yuav kawg ua nws los ntawm kev hu nws txoj kev khiav thiab hla cov lus rau nws. Txij li thaum cov kev hu xov tooj no yuav ib txwm tshwm sim nyob rau hauv qhov kev txiav txim ntawm cov lus tau txais ntawm tib lub xov, nws tso cai rau koj los txheeb xyuas cov xwm txheej.
Tib neeg kuj nug, siv tus handler yog dab tsi?
A Tus tuav tso cai rau kev sib txuas lus rov qab nrog UI xov los ntawm lwm cov xov keeb kwm yav dhau. Qhov no muaj txiaj ntsig hauv hauv raws li hauv tsis tso cai rau lwm cov xov sib txuas lus ncaj qha nrog UI xov. A Tus tuav tso cai rau koj xa thiab ua Message thiab Runnable khoom txuam nrog ib tug xov's MessageQueue.
Tsis tas li ntawd, Handler class salesforce yog dab tsi? Hauv ib Salesforce context, ib tug trigger tus tuav yog qhov pib taw tes rau 'kuav' complex logic teem rau hauv ib tug txhais. Tsim ib chav kawm txhais raws li MyObjectTriggerHandler tuaj yeem pab tsim cov txheej txheem ntawm cov khoom siv rov qab siv tau uas tswj hwm txhua qhov haujlwm kom ua tiav los ntawm qhov tshwm sim.
Raws li, dab tsi yog tus thawj tswj chav kawm hauv Java?
Tus Thawj Saib Xyuas Chav Kawm . java ua .lang. Object javax.media. Tus thawj tswj pej xeem zaum kawg Tus Thawj Tswj chav kawm txuas ntxiv java ua .lang. Object. Tus thawj tswj yog qhov chaw nkag tau rau kev tau txais cov kev pabcuam raws li cov neeg ua si, DataSources, thiab lub kaw lus TimeBase.
Dab tsi yog runnable hauv Java?
Khiav tau interface hauv Java . java ua . lang. Khiav tau yog ib qho interface uas yuav tsum tau ua los ntawm cov chav kawm uas nws qhov xwm txheej yog npaj los ua kom tiav los ntawm cov xov. Tsis tas yuav tsum tau subclassing Xov thaum ib txoj hauj lwm yuav ua tau los ntawm overriding nkaus xwb run() txoj kev ntawm Khiav tau.
Pom zoo:
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