Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 v
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 5/.W-Q\pl}
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 EjP;P}_iK
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分页支持类: M=,pn+}y>
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java代码: V.B@@ ;
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package com.javaeye.common.util; poz_=,c
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import java.util.List; kpgvAKyx
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publicclass PaginationSupport { 3lF"nv
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publicfinalstaticint PAGESIZE = 30; L;V8c
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privateint pageSize = PAGESIZE; -y.cy'$f
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{
privateList items; -Y_,
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privateint totalCount; t$BjJ -G
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privateint[] indexes = newint[0]; ;Gr
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privateint startIndex = 0; \[9VeqMU
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public PaginationSupport(List items, int m]qw8BoU`F
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totalCount){
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setPageSize(PAGESIZE); jE0oLEg&
setTotalCount(totalCount); ^Iw$(
setItems(items);
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setStartIndex(0); $>)0t@[f
} M 5#wz0
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public PaginationSupport(List items, int oN032o?S
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totalCount, int startIndex){ ^50dF:V(1
setPageSize(PAGESIZE); TFXBN.?9T
setTotalCount(totalCount); x/,;:S
setItems(items); 12 p`ZD=
setStartIndex(startIndex); 9E7 G%-
} t}+/GSwT
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public PaginationSupport(List items, int rC8p!e.yL
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totalCount, int pageSize, int startIndex){ &nEL}GM)E
setPageSize(pageSize); |k.'w<6mb9
setTotalCount(totalCount); ]p! {
setItems(items); xmg3,bO
setStartIndex(startIndex); eiK_JPF A-
} b
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publicList getItems(){ _LJF:E5L
return items; Sa g)}6+
} W
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publicvoid setItems(List items){ #E]K*mE'
this.items = items; #/>TuJc
} R4p Pt
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publicint getPageSize(){ z0[@O)Sj
return pageSize; KF(H
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} 4aO/^Hl
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publicvoid setPageSize(int pageSize){ $tZ
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this.pageSize = pageSize;
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} SAP/jD$5]>
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publicint getTotalCount(){ \_Bj"K
return totalCount; P j
} t/;2rIx>
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publicvoid setTotalCount(int totalCount){ !!C/($
if(totalCount > 0){ 8}|et~7!
this.totalCount = totalCount; f~VlCdf+
int count = totalCount / R XCn;nM4
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pageSize; >9H^r\
if(totalCount % pageSize > 0) ^_]ZZin
count++; +d3|Up8=
indexes = newint[count];
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for(int i = 0; i < count; i++){ A3eCI
indexes = pageSize * J?o
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} wv9HiHz8gD
}else{ !v}TRGX
this.totalCount = 0; bWTfP8gT
} aqON6|6K
} ) H,Xkex
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publicint[] getIndexes(){ }zGx0Q
return indexes; |.k'?!
} D?n6h\h\$%
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publicvoid setIndexes(int[] indexes){ ?c#s}IH
this.indexes = indexes; -Q20af-
} c5ij2X|I
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publicint getStartIndex(){ 9,?~dx
return startIndex; WE\TUENac(
} R/=rNUe
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publicvoid setStartIndex(int startIndex){ CXq[VYM&X
if(totalCount <= 0) 4\n
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this.startIndex = 0; >ai,6!
elseif(startIndex >= totalCount)
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this.startIndex = indexes L$5,RUy
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[indexes.length - 1]; FJ3S
elseif(startIndex < 0) eIvZhi
this.startIndex = 0; phy}Hk/
else{ av'm$I|O
this.startIndex = indexes o h{>nwH
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[startIndex / pageSize]; 2 5 \S>
} e"hfeNphz
} Uj5-x%~
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publicint getNextIndex(){ gWr7^u&q@|
int nextIndex = getStartIndex() + 'WW:'[Syn'
@}
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pageSize; 0=>$J
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if(nextIndex >= totalCount) Qj^Uz+b
return getStartIndex(); CV0id&Nv
else QXb2jWz
return nextIndex; L"b&O<No
} Bt<)1_
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publicint getPreviousIndex(){ kp*v:*
int previousIndex = getStartIndex() - lsax.uG5x
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pageSize; ;+~5XLk
if(previousIndex < 0) O h@z<1eYZ
return0; h`6 (Oo|
else u
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return previousIndex; <q7o"NI6FZ
} T]\1gs41
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} GlJ[rD
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抽象业务类 Y#os6|MV#
java代码: >` s"C
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/** Tf3CyH!k
* Created on 2005-7-12 S/E&&{`ls
*/ "WKOlfPa
package com.javaeye.common.business; 4v_Ac;2m&
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import java.io.Serializable; ,SIS3A>s
import java.util.List; DXf
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import org.hibernate.Criteria; /5sn*,
import org.hibernate.HibernateException; {8.Zb NEJ
import org.hibernate.Session; z@`o(gh
import org.hibernate.criterion.DetachedCriteria; {dF@Vg_n
import org.hibernate.criterion.Projections; L -Q8iFW'
import #zP-,2!r
@V
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org.springframework.orm.hibernate3.HibernateCallback; $+80V{J#
import DzR,ou
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org.springframework.orm.hibernate3.support.HibernateDaoS ,8384'
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upport; Un]wP`
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import com.javaeye.common.util.PaginationSupport; ^;F/^_
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public abstract class AbstractManager extends 8-<F4^i_i
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HibernateDaoSupport { qU#A,%kcV
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7{\
privateboolean cacheQueries = false; 2q[pOT'k
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privateString queryCacheRegion; fnX[R2KZ
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publicvoid setCacheQueries(boolean syr0|K[
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cacheQueries){ SA'g`
this.cacheQueries = cacheQueries; 'ayb`
} i@9
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publicvoid setQueryCacheRegion(String &-*l{"7p+%
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queryCacheRegion){ 8)S)!2_h
this.queryCacheRegion = y^H5iB[SPL
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queryCacheRegion; +2{ f>KZ
} rfonM~3?'
- ;gQy[U
publicvoid save(finalObject entity){ '=;e#
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getHibernateTemplate().save(entity); F`4W5~`
} x:-NTW
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publicvoid persist(finalObject entity){ Ct'tUF<K5
getHibernateTemplate().save(entity); n>)aw4
} &vmk!wAs
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publicvoid update(finalObject entity){ WdOxwsq"
getHibernateTemplate().update(entity); (RI)<zaK
;
} %ap]\o$^4
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publicvoid delete(finalObject entity){ -,/7u3
getHibernateTemplate().delete(entity); 0y|1@CS
} ';G/,wB?`
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publicObject load(finalClass entity, PV\J]
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finalSerializable id){ c!HGiqp
return getHibernateTemplate().load oOprzxf"+Z
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(entity, id); oU)(/
} !%$[p'
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publicObject get(finalClass entity, _
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finalSerializable id){ B=*0
return getHibernateTemplate().get IiniaVuQ
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(entity, id); :uAL(3pQ
} (^W}uDPCB
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publicList findAll(finalClass entity){ U~=?I)Ni
return getHibernateTemplate().find("from 2W0nA t
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" + entity.getName()); hRXnig{;3
} +FNGRL
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publicList findByNamedQuery(finalString >e;jGk?-
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namedQuery){ 1
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return getHibernateTemplate ~Q=;L>Qd
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().findByNamedQuery(namedQuery); oC"
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} {$EX :ID
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publicList findByNamedQuery(finalString query, wxBHlgK4z
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finalObject parameter){ 3]1 !g6
return getHibernateTemplate '?$@hqQn
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().findByNamedQuery(query, parameter); |};d:LwX
} #qVvh3#g
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publicList findByNamedQuery(finalString query, RNB-W%
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finalObject[] parameters){ KRGj6g+
return getHibernateTemplate 9.xb-m7
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().findByNamedQuery(query, parameters); zU[o_[+7^
} +h-% {
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publicList find(finalString query){ *b~8`Opa`
return getHibernateTemplate().find 8r>\scS
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(query); #SHJ0+)o
} /*gs]
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publicList find(finalString query, finalObject CV
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parameter){ dSjO12b
return getHibernateTemplate().find 7_3 6xpw
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(query, parameter); "E7<S5cr
} e\ (X:T
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public PaginationSupport findPageByCriteria tWl')^
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(final DetachedCriteria detachedCriteria){ ir}*E=*
return findPageByCriteria u0)O Fz
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); M&=SvM.f
} fiC0'4.,
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public PaginationSupport findPageByCriteria 0-OKbw5%=b
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(final DetachedCriteria detachedCriteria, finalint <gX({FA
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startIndex){ JkR%o
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return findPageByCriteria noaR3)
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(detachedCriteria, PaginationSupport.PAGESIZE, `[E-V
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startIndex); C:&Sk\
} wGMoh.GTh
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public PaginationSupport findPageByCriteria 3;b)pQ~6CJ
C &@'oLr
(final DetachedCriteria detachedCriteria, finalint 1LFad>`
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pageSize, yS
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finalint startIndex){ `tO t+>YWn
return(PaginationSupport) @lM-+q(tl
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getHibernateTemplate().execute(new HibernateCallback(){ ,;YNI
publicObject doInHibernate 3
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(Session session)throws HibernateException { (e_p8[x
Criteria criteria = VxOWv8}|
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detachedCriteria.getExecutableCriteria(session); 1Cc91
int totalCount = /xSJljexz
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((Integer) criteria.setProjection(Projections.rowCount zGme}z;1@
KN@ [hb7%
()).uniqueResult()).intValue(); s hq
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criteria.setProjection ^^k9Acd~p
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(null); \N0wf-qa=
List items = |0p@'X1
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criteria.setFirstResult(startIndex).setMaxResults o=7e8l
.|DrXJ\c
(pageSize).list(); 5m@'( ]j
PaginationSupport ps = qoT&N,/
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new PaginationSupport(items, totalCount, pageSize, 3y$6}Kp4?
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startIndex); EBWM8~Nm#
return ps; _8SB+s*
} ])v61B
}, true); IrRe6nf@K
} F`F|.TX
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public List findAllByCriteria(final LB.B w
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DetachedCriteria detachedCriteria){ p4\sKF8-
return(List) getHibernateTemplate y] 9/Xr/
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().execute(new HibernateCallback(){ 9;n*u9<
publicObject doInHibernate ZLVgK@l
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(Session session)throws HibernateException { ,[N(XstI
Criteria criteria = Pdh`Gu1:3
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detachedCriteria.getExecutableCriteria(session); usK P9[T$
return criteria.list(); c|'$3dB*
} ,QA=)~;D
}, true); KDf#e3
} v0!(&g3Sd
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public int getCountByCriteria(final *Vb#@O!
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DetachedCriteria detachedCriteria){ :%28*fl
Integer count = (Integer) jL)Y'
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getHibernateTemplate().execute(new HibernateCallback(){ GaJE(N
publicObject doInHibernate VqD_FS;E
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(Session session)throws HibernateException { RV]QVA*i
Criteria criteria = U![$7k>,pr
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detachedCriteria.getExecutableCriteria(session); n0K+/}m
return xe.f]a
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criteria.setProjection(Projections.rowCount rHybP6C<
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()).uniqueResult(); PktnjdFV
} p.MLKp-'
}, true); KqBiF]Q
return count.intValue(); -W/D Cj<
} 3*{l^<`:gA
} #;1RStb:zj
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用户在web层构造查询条件detachedCriteria,和可选的 :vS/Lzk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 c/F!cW{z^
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PaginationSupport的实例ps。 |Ul 4n@+2
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ps.getItems()得到已分页好的结果集 &liFUP?
ps.getIndexes()得到分页索引的数组 1Qjc*+JzO.
ps.getTotalCount()得到总结果数 vUL@i'0&o
ps.getStartIndex()当前分页索引 S@
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ps.getNextIndex()下一页索引 ht+wi5b
ps.getPreviousIndex()上一页索引 @QYCoEU8J
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _S*QIbO
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 "cOBEhn%l
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一下代码重构了。 P $r!u%W
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我把原本我的做法也提供出来供大家讨论吧: VVuNU"-
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首先,为了实现分页查询,我封装了一个Page类: I;<__
java代码: l4I',79l
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/*Created on 2005-4-14*/ 3EA_-?
package org.flyware.util.page; OzxiT +
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/** od !s5f!
* @author Joa QY\'Uu{
* `$JOFLa
*/ W3X;c*j
publicclass Page { or)fx/ %h
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/** imply if the page has previous page */ ,W]}mqV%.'
privateboolean hasPrePage; Sl
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h7xgLe@
/** imply if the page has next page */ h-m0Ro?6
privateboolean hasNextPage; h,/3}
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/** the number of every page */ ep
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privateint everyPage; O
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-O@/S9]S)
/** the total page number */ 6hFs{P7
privateint totalPage; "`pg+t&
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/** the number of current page */ ,yfJjV*I
privateint currentPage; &Ci_wDJ
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/** the begin index of the records by the current <rU+{&FKNL
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query */ 20Rm|CNH?
privateint beginIndex; ZS&lXgo
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/** The default constructor */ Z#GR)jb+
public Page(){ \x_$Pu
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} On+0@hh
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/** construct the page by everyPage Xs2B:`,hh
* @param everyPage nF
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* */ :mdoGb$dr
public Page(int everyPage){ V* ,u;*
this.everyPage = everyPage; b#S-u }1PE
} YIl,8!
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/** The whole constructor */ OJ7y
public Page(boolean hasPrePage, boolean hasNextPage, ?xE'i[F @
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XpT})AV
int everyPage, int totalPage, a7]Z_Gk
int currentPage, int beginIndex){ hg `N`O
this.hasPrePage = hasPrePage; ,nw5 M.D_
this.hasNextPage = hasNextPage; )VG_Y9;Xk:
this.everyPage = everyPage; H
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this.totalPage = totalPage; hSk
this.currentPage = currentPage; S~ y.>X3"P
this.beginIndex = beginIndex; z+?48}
} i_$?sg#=yk
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/** 7.
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* @return h{PJ4U{W
* Returns the beginIndex. [} %=&B
*/ 0B5d $0
publicint getBeginIndex(){ ]mi)x63^
return beginIndex; ^;EwZwH[
} O(T6Y80pU
G?+]BIiL
/** mldY/;-H!1
* @param beginIndex G;AV~1i:~
* The beginIndex to set. !j0iLYo(*
*/ \=@4F^U7`
publicvoid setBeginIndex(int beginIndex){ WjBtL52
this.beginIndex = beginIndex; w< |Lx#L}
} *jy"g64j
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/** x=Ez hq]X
* @return K$
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* Returns the currentPage. ~A>-tn}O
*/ >DR/lBtL
publicint getCurrentPage(){ 3^F1 hCB
return currentPage; H4e2#]*i7
} Q,\S3>1n
42
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/** S^@#%>
* @param currentPage [\"<=lb`
* The currentPage to set. gL wNHS
*/ .wuRT>4G)G
publicvoid setCurrentPage(int currentPage){ 7"k\i=
this.currentPage = currentPage; yL3F
} oeG?2!Zh
p,2H8I){
/** 9/5EyV
* @return tkhEjTZ
* Returns the everyPage. -k3WY&9,
*/ ]8XIw`:f
publicint getEveryPage(){ #U/L8
return everyPage; aDX4}`u
} Qlhm:[
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/** 2!Pwg0%2
* @param everyPage 2{)<Df@
* The everyPage to set. V5d|Lpm
*/ `b[@GGv
publicvoid setEveryPage(int everyPage){ :,MI,SwnS
this.everyPage = everyPage; ~*G}+Ur$2
} vg[zRWh8
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/** j(Tk6S
* @return ?h ym~,
* Returns the hasNextPage. +D#.u^
*/ 8X=2# &)
publicboolean getHasNextPage(){ "I45=nf
return hasNextPage; 9h^TOZK)
} g);.".@"
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/** )Z@hk]@?_[
* @param hasNextPage q62U+o9G
* The hasNextPage to set. ]+AgXUrbOD
*/ 4{ exv
publicvoid setHasNextPage(boolean hasNextPage){ ; HjT
this.hasNextPage = hasNextPage; 2v1dSdX,W
} 6NzS <
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/** 1?#Wg>7'
* @return X\]Dx./
* Returns the hasPrePage. qk\LfRbj
*/ ig:z[k?
publicboolean getHasPrePage(){ \&%y4=y<sE
return hasPrePage; 7o`pNcabtz
} ZvW&%*k=
O9MBQNwjA
/** z%WOv~8~
* @param hasPrePage `k'Dm:*`u4
* The hasPrePage to set. AG,;1b,:81
*/ Kl+4A}Uo
publicvoid setHasPrePage(boolean hasPrePage){ dY]iAJ
this.hasPrePage = hasPrePage; b]5S9^=LI
} '5SO3/{b
4S,/Z{ J.
/** D$bJ s O
* @return Returns the totalPage. <e' l"3+9(
* vTYgWR,h
*/ }{
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publicint getTotalPage(){ \E2S/1p
return totalPage; h>jp.%oOu
} [IW6F
15`,kJSK
/** }zV#?;}
* @param totalPage 3})0p
* The totalPage to set. 1
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*/ &pLCN[a
publicvoid setTotalPage(int totalPage){ ]7_O#MY1
this.totalPage = totalPage; 97SG;,6
} tsqWnz=)
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} ogKd}qTov
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 %c,CfhEV%&
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个PageUtil,负责对Page对象进行构造: {_*$X
java代码: >{kPa|
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/*Created on 2005-4-14*/ d9uT*5f
package org.flyware.util.page; 9w,u4q
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import org.apache.commons.logging.Log; 4\EvJg@Z.
import org.apache.commons.logging.LogFactory; 1'g{tP"d
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/** W/|C
* @author Joa @V#
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* lIF*$#`oh*
*/ {uMqd-Uu
publicclass PageUtil { ;X2 (G
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privatestaticfinal Log logger = LogFactory.getLog 5mYI5~
p
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(PageUtil.class); ]gGCy '*)
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/** VNLggeX'U
* Use the origin page to create a new page db.E-@W.OI
* @param page 2VNfnk
* @param totalRecords y[@<goT
* @return cxQ8/0^
*/ :,(ZMx\
publicstatic Page createPage(Page page, int N%&D(_
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totalRecords){ 1z[GY RSt
return createPage(page.getEveryPage(), y:+s*x6Vg
~_Mz05J-\_
page.getCurrentPage(), totalRecords); NQ(}rr'.
} `L=$,7`
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/** 5=.EngG
* the basic page utils not including exception 35[8XD
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handler =
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* @param everyPage /RmHG
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* @param currentPage _}B:SM
* @param totalRecords R?Or=W)i
* @return page ~:%rg H
*/ |cBpX+D
publicstatic Page createPage(int everyPage, int nC5
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currentPage, int totalRecords){ &`'gO
9
everyPage = getEveryPage(everyPage); O$=)
currentPage = getCurrentPage(currentPage); mJ|7Jc
int beginIndex = getBeginIndex(everyPage, 8\^[@9g3\3
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currentPage); k(;c<Z{?1
int totalPage = getTotalPage(everyPage, ^f,('0p->
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totalRecords); vK\;CSk
boolean hasNextPage = hasNextPage(currentPage, oGLSk(T&I
K>`7f]?H*e
totalPage); E@_M|=p&
boolean hasPrePage = hasPrePage(currentPage); nJ4CXSdE
e1RtoNF ^
returnnew Page(hasPrePage, hasNextPage, 7^J-5lY3S
everyPage, totalPage, J
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currentPage, zAxwM-`
q#RVi8('
beginIndex); WqC6c&NM
} TvWhy`RQ
;mLbJT
privatestaticint getEveryPage(int everyPage){ 2Ax HhD.
return everyPage == 0 ? 10 : everyPage; Tdr^~dcQ
} [-sE:O`yt
[N/[7Q/y
privatestaticint getCurrentPage(int currentPage){ @:. 6'ji,`
return currentPage == 0 ? 1 : currentPage; gi7As$+E
} n8M/Y}mH
M,Px.@tw.
privatestaticint getBeginIndex(int everyPage, int *s6MF{Ds
pAV}hB
currentPage){ T@]vjXd![
return(currentPage - 1) * everyPage; (r^IW{IndX
} PaEsz$mgy
t
_Q/v
privatestaticint getTotalPage(int everyPage, int x=qACoq
jBEt!Azur
totalRecords){ XRI1/2YA
int totalPage = 0; kl| KFdA;
!o 7uZC\
if(totalRecords % everyPage == 0) .JpYZ |
totalPage = totalRecords / everyPage; BcT|TX+ct
else 1Ly?XNS
totalPage = totalRecords / everyPage + 1 ; )G6]r$M>o0
qfY.X&]PU
return totalPage; 2I'\o7Y
} Wv"[,5
Z13
'Z7oPq6
privatestaticboolean hasPrePage(int currentPage){ 0n_Cuh\
return currentPage == 1 ? false : true; O4&/g-
} IjDG
'7W?VipU
privatestaticboolean hasNextPage(int currentPage, fwI Zr~l
U3^T.i"R
int totalPage){ eN%Ks
return currentPage == totalPage || totalPage == Y:VM5r)
I/GZ
0 ? false : true; %f@VOSs
} C/[2?[
Z$,1Tk"O/s
dox QS ohS
} "$#x+|PyC
6yF4%Sz9
Ckvm3r\i2
j*$GP'Df3
%.b)%=
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 SM:{o&S`
lE[LdmwDrb
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 _qmBPUx
~]A';xH&
做法如下: k-T_,1l{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~?6V-m{>#
^<<( }3
的信息,和一个结果集List: d?&?$qf[
java代码: q!<`ci,uS
R6)p4#|i
$RKd@5XP
/*Created on 2005-6-13*/ &tQ,2RT
package com.adt.bo; 'mug,jM
,I@4)RSAH|
import java.util.List; uwWfL32
.Kq>/6
import org.flyware.util.page.Page; (XRj##G{
T |'Ur#
/** vUgLWd
* @author Joa bK("8T\?
*/ S53 [Ja
publicclass Result { _>A])B
^
}k<b)I*A
private Page page; R8\y|p#c
_e8@y{/~Fd
private List content; S,3e|-&$
^$_ifkkLz
/** +]CKu$,8
* The default constructor IVkKmO(qO
*/ eJ%~6c`@!
public Result(){ $z{HNY*2
super(); QD<^VY6
} !V@Y \M
d
v<tH 3I+
/** \9i.dF
* The constructor using fields klUxt?-
* !U,qr0h
* @param page q&Q* gEFK
* @param content n4k.tq
*/ 8o4<F%ot
public Result(Page page, List content){ F!`.y7hY@
this.page = page; g=b[V
this.content = content; $|6Le;
K
} cdP+X'Y4D
))G%C6-
/** Si*Pi
* @return Returns the content. GMgsM6.R
*/ d)r=W@tF]
publicList getContent(){ \D, 0
return content; ,`/!0Wmt
} ui G7
Fdu0?H2TL
/** yKOf]m>#
* @return Returns the page. 5&2=;?EO
*/ `W?aq]4x5
public Page getPage(){ 2;[75(l6|}
return page; `z5j
} Xj+1]KRN
|m k $W$h
/** j=dHgnVvj
* @param content PM=I
* The content to set. SP
HeI@i
*/ ~LO MwMHl
public void setContent(List content){ vCbqZdy?
this.content = content; 4p>@UB&U
} 9Wx q
5
;dg#hO
/** gA2\c5F<
* @param page ]ueq&|
* The page to set. [:g6gAuh,
*/ bMkn(_H)\
publicvoid setPage(Page page){ <LZvG IMl
this.page = page; 3{on$\
} # dW$"u
} ,O3"r;
#hR}7K+@
A>7'W\R
pK*-In
\RMYaI^+;
2. 编写业务逻辑接口,并实现它(UserManager, u33+ ikYv
&}:Hp9n
UserManagerImpl) B{s[SZ
java代码: RXl52#:
NqhRJa63
b0LQ$XM>8
/*Created on 2005-7-15*/ ~O@V;y
package com.adt.service; RF g$N@g,
zMtK_ccQ
import net.sf.hibernate.HibernateException; <&l3bL
4X#>;
import org.flyware.util.page.Page; 2lAuO!%
I9SO}a2p
import com.adt.bo.Result; 8C4Tyms
HOykmx6$
/** lP9a*>=a
* @author Joa :Nc~rOC_
*/ ",&}vfD4M
publicinterface UserManager { _a15R/S
j]Rl1~+M
public Result listUser(Page page)throws KMoRMCT
qYsu3y)*N
HibernateException; Y/gVyQ(
1mI)xDi9
} w4(DR?[nC
w`>xK
sKW>
d<7xSRC
!R{L`T0
QhpE 2ICU
java代码: Z?"Pkc.Ei
/MQd [03]
2$[u&__E
/*Created on 2005-7-15*/ {hg,F?p
'
package com.adt.service.impl; CmJ*oXyi
hs<7(+a
import java.util.List; n2(~r
'r)
mqq~&nI
import net.sf.hibernate.HibernateException; 8.Y6r
^U~YG=!ww
import org.flyware.util.page.Page; LsV!Sd
import org.flyware.util.page.PageUtil; L8 R|\Bx
$D9JsUij
import com.adt.bo.Result; wQM(Lm#Q
import com.adt.dao.UserDAO; C+y:<oo)
import com.adt.exception.ObjectNotFoundException; y3;G<9K2c]
import com.adt.service.UserManager; ix7N q7!N
&)xoR4!2
/** bmt2~!
* @author Joa c?<FMb3]
*/ ##k=='dR
publicclass UserManagerImpl implements UserManager { N<N!it
r<&d1fM;X
private UserDAO userDAO; *e_ /D$SC
<]CO}r
/** tQ?? nI2
* @param userDAO The userDAO to set. oB_{xu$6|
*/ Q6.},o
publicvoid setUserDAO(UserDAO userDAO){ \8_&@uLm
this.userDAO = userDAO; L2Gm0 v
}
]MUuz'<
Eg
w ?
/* (non-Javadoc) 3ufUB^@4v
* @see com.adt.service.UserManager#listUser 5zfaqt`
KS(s<ip|
(org.flyware.util.page.Page) {CQA@p:Y}
*/ lQ!6n
public Result listUser(Page page)throws !u\ X,.h
]d% hU
HibernateException, ObjectNotFoundException { s=U_tfpH
int totalRecords = userDAO.getUserCount(); ZL1[Khr,s
if(totalRecords == 0) lXv{+ic
throw new ObjectNotFoundException "V?U^L>SF
\i`/k(
("userNotExist"); E8FS jLZ
page = PageUtil.createPage(page, totalRecords); (F$q|qZ%
List users = userDAO.getUserByPage(page); gfih;i.pY
returnnew Result(page, users); s\>$ K%!H?
} ]<z>YyBA
h\D
y(\
}
5OKbW!
q'c'rN^
pmQ9iA@=
(zgXhx_!D
9.1%T06$
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fS!%qr
#\t?`\L3
询,接下来编写UserDAO的代码: %G\rL.H|
3. UserDAO 和 UserDAOImpl: zbi[r
java代码: Du[$6
uv9cOd
SBeb}LZ
/*Created on 2005-7-15*/ 8LR_K]\
package com.adt.dao; ir%/9=^d
#XC\=pZX
import java.util.List; ">CjnF2>R
q|gG{9
import org.flyware.util.page.Page; [gH
vI
:[\}Hn=
import net.sf.hibernate.HibernateException; 7CM<"pV
Q> @0'y=s
/** ivw2EEo,
* @author Joa WBTX~%*U
*/ `sJkOEc`
publicinterface UserDAO extends BaseDAO { ?L{[84GSO
hQ8/-#LO_
publicList getUserByName(String name)throws f5d"H6%L
tR0o6s@v/<
HibernateException; A9$q;8= <
qBKIl=
ne
publicint getUserCount()throws HibernateException; ETjlq]@j
vxZz9+UbF
publicList getUserByPage(Page page)throws 2hmV1gj
x*bM C&Ea
HibernateException; KcNEB_i
\gj@O5rG P
} }2V|B4
3x'BMAA+
*Swb40L^
b/5;377_
/-G;#Wm
java代码: ~G5)ya-
<\2,7K{{+;
j"J2&Y2
/*Created on 2005-7-15*/ M<g>z6
package com.adt.dao.impl; LuR.; TiW
9$UjZ$ v
import java.util.List; (K^9$w]tf
VEo>uR
import org.flyware.util.page.Page; R}>Gk
wdl6dLu
import net.sf.hibernate.HibernateException; 7P=1+2V
import net.sf.hibernate.Query; 2-]gHAw%
8cR4@Hqx
import com.adt.dao.UserDAO; ^Zydy
V0ulIKck
/** ]rC6fNhQ
* @author Joa q9icj
*/ '$q'Wl)
public class UserDAOImpl extends BaseDAOHibernateImpl 8Ay#6o
YG"P:d;s
implements UserDAO { &xrm;pO
"fr B5[
/* (non-Javadoc) V A4_>6
* @see com.adt.dao.UserDAO#getUserByName C37KvLQ
fLct!H3
(java.lang.String) f=g/_R2$xN
*/ ^<[oKi;>
publicList getUserByName(String name)throws ZDcv-6C)B
(lS&P"Xi
HibernateException { )k <ON~x
String querySentence = "FROM user in class O' A''}M
D8BK/E-
com.adt.po.User WHERE user.name=:name"; URX>(Y}g9^
Query query = getSession().createQuery MDl
1ciP+->$
(querySentence); w*$nG$
query.setParameter("name", name); sqj8c)6
return query.list(); )uZ<?bkQ
} >vt#,8VAN
sAC1Pda
/* (non-Javadoc) @&mv4zz&W
* @see com.adt.dao.UserDAO#getUserCount() ) dwPD
*/ :=UeYm
@
publicint getUserCount()throws HibernateException { Lt|k}p@]
int count = 0; UH.M)br
String querySentence = "SELECT count(*) FROM !|!:MYn
}oj$w?Ex
user in class com.adt.po.User"; se2+X>@>
Query query = getSession().createQuery +%$!sp?
m"X0Owx
(querySentence); :}o0Eb
count = ((Integer)query.iterate().next )?I1*(1{A
.nKyB'uV
()).intValue(); "4&HxD8_ih
return count; =>4>Z_q
} G@
BrU q
l3b$b%0'
/* (non-Javadoc) k]ptk^
* @see com.adt.dao.UserDAO#getUserByPage KX[_eOL
>bEH&7+@_'
(org.flyware.util.page.Page) 2
os&d|
*/ I6{}S6
publicList getUserByPage(Page page)throws OZQhT)nS]
9@:H9"w
HibernateException { #@3RYx
String querySentence = "FROM user in class Pm#B'N#*N|
W>bhSKV%
com.adt.po.User"; !+JSg uy
Query query = getSession().createQuery %* vYX0W"
c^Rz?2x
(querySentence); 3yZtyXRPn
query.setFirstResult(page.getBeginIndex()) (ZT*EFhb(
.setMaxResults(page.getEveryPage()); ol:,02E&
return query.list();
P\*-n"
} ?dC[VYC\^
S2;{)"mS
} ,BOB &u
2JUX29rER
^qy$M>
M!;H3*
2RT9Q!BX{
至此,一个完整的分页程序完成。前台的只需要调用 rV[#4,} PF
:-Ho5DHg
userManager.listUser(page)即可得到一个Page对象和结果集对象 q'hMf?_
*8kg6v%
的综合体,而传入的参数page对象则可以由前台传入,如果用 4~ZQsw`
#W~5M ?+
webwork,甚至可以直接在配置文件中指定。 /n/U)!tp
W6E9
下面给出一个webwork调用示例: f(|qE(
java代码: 0{gvd"q
v>~ottQ|
lk2F]@_kJH
/*Created on 2005-6-17*/ 05=O5<l
package com.adt.action.user; PF1!aAvVb
i ao/l
import java.util.List; aluXh?
WFjNS'WI_
import org.apache.commons.logging.Log; j K$4G.x
import org.apache.commons.logging.LogFactory; nwOr
import org.flyware.util.page.Page; |hiYV
+}I[l,,xy
import com.adt.bo.Result; h"
P4
import com.adt.service.UserService; j/#kO?
import com.opensymphony.xwork.Action; NA]7qb%%<
*~lD;{2
/** ;]i&AAbj
* @author Joa RR75ke[Hs
*/ pIC CjA?3@
publicclass ListUser implementsAction{ [j
'Ogm7"
V%<<Udu<
privatestaticfinal Log logger = LogFactory.getLog bqsb (C
d[kb]lC
(ListUser.class); *P61q\2Z
i"F'n0*L
private UserService userService; +r2E5s
f8lB xK
private Page page; NQ'^z
B5 C]4
privateList users; ?0DCjh8We
#fk)Y1
/* /h0-qW
* (non-Javadoc) 0{BPT>'
* ^ B=x-G.
* @see com.opensymphony.xwork.Action#execute() v"F.<Q
*/ dt',)i8D
publicString execute()throwsException{ one^XYy1%
Result result = userService.listUser(page); _B8e1an
page = result.getPage(); 2t<
dCw
users = result.getContent(); f"k?Ix\
e
return SUCCESS; !_?<-f(
} $P866F
7B"J x^
/** 0`h[|FYV
* @return Returns the page. KQJn\#>
*/ {l0;G)-
public Page getPage(){ P qagep d
return page; 69dFd!G\
} [{}9"zB$x0
h|!B;D
/** ^W_}Gd<-#Y
* @return Returns the users. ^n@iCr9
*/ (e=ksah3>
publicList getUsers(){ s|pb0
return users; u5H#(&Om
} } <2F]UuR
a_waLH/
/** }(ay(
* @param page Te[[xhTyw
* The page to set. KfG%#2\G_
*/ yx{Ac|<mR
publicvoid setPage(Page page){ UciWrwE
this.page = page;
CV]PCq!
} `DG6ollp{
)N)ziAy}
/** :`:<JA3,
* @param users R>/M>*C
* The users to set. g"(N_sv?
*/ pcur6:8W!
publicvoid setUsers(List users){ c*RZbE9k
this.users = users; K[~Wj8W0
} o4w+)hh
-fL|e/
/** nI2}E
* @param userService 0WF(Ga/o
* The userService to set. O<6/0ub&+h
*/ l>~:lBO
publicvoid setUserService(UserService userService){ X2M<DeF:
this.userService = userService; puZ<cV
e/
} ~q4DePVE
} kgr:85
O3bK>9<K
zHb<YpU
4 3]6J]!)
:e+GtN?
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, e!tgWYN
<' P|g
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 1G.+)*:3
aCGPtA'
么只需要: _9!Ru!u~
java代码: k_P`t[YZV
T2Y`q'
R&ou4Y:DG
<?xml version="1.0"?>
`c :'il?
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 7c
%@2
&sS k~:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _j%Rm:m;<
,J}lyvkd
1.0.dtd"> M8KfC!
Z"Et]xSU%$
<xwork> Sw5H+!
lz{>c.Ll[
<package name="user" extends="webwork- 1 _5[5K^
C>T6{$xkC
interceptors"> !~ -^s
x-tA{_:
<!-- The default interceptor stack name wTIf#y1=9
-)y"EJ(N
--> ;Jx ^
<default-interceptor-ref OR?8F5o?p
]\#RsVX
name="myDefaultWebStack"/> *\S>dhJ4
{/QpEd>3+
<action name="listUser" ?a}eRA7
xZ;';}&pj
class="com.adt.action.user.ListUser"> X\1D[n:
<param ngm7Vs
{F@;45)o
name="page.everyPage">10</param> |I OTW=>
<result Rx`0VQ
QO#ZQ~
name="success">/user/user_list.jsp</result> l\$C)q6O
</action> QRdb~f;<hj
n8:2Z>
</package> y:2o-SJn
q8kt_&Ij
</xwork> "hy#L
0\t
"H G:by
R`1$z8$
zR{TWk]
gvcT_'
nF=Ig-NX^
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 4a!L/m*
jU4Ir{f
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 zcxG%? Q
S?Eg
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 8De
`.!Gg
o,aI<5"
|?g2k:fzB7
w~Y#[GW
8uI^ B
我写的一个用于分页的类,用了泛型了,hoho !. 0W?6yo
X(WG:FP27
java代码: 6?,r d
~)ByARao=
q5HHMHB
package com.intokr.util; OmoY] 8N}
Q'A->I<;_s
import java.util.List; (1Kh9w:^"
M2oKLRt)L
/** c!841~p(Q
* 用于分页的类<br> .pdgRjlSn
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?^"S%Vb
* 7gJy xQ
* @version 0.01 0;XnNz3&
* @author cheng }>0UaK
*/ \lY26'
public class Paginator<E> { w6wXe_N+M
privateint count = 0; // 总记录数 [6/%ynlP
privateint p = 1; // 页编号 ;$%+TN
privateint num = 20; // 每页的记录数
Pt1Htt:BE
privateList<E> results = null; // 结果 aqyXxJS8
P,>#
/** p1|@F^Q
* 结果总数 H>Fy 2w
*/ CV&
SNA
publicint getCount(){ 90ORx\Oeo
return count; 4Yn*q~f
} q-!m|<Z
dvXu?F55
publicvoid setCount(int count){ #MBYa&Tw7
this.count = count; #[i({1`^L
} xknP
`T
=E,*8O]
/** sX**'cH
* 本结果所在的页码,从1开始 W5yqnjK
$4
* Fh?q;oEj
* @return Returns the pageNo. YE^|G,]
*/ Ybok[5
publicint getP(){ 6~2!ZU
return p; $Z;0/\r%
} EL+}ab2S
;ga~ae=Fg
/** Z+vLEEX*uQ
* if(p<=0) p=1 4)"jg[
* N*$Q(K
* @param p e{?~m6
*/ 7,(:vjIXd
publicvoid setP(int p){ ].Et&v
if(p <= 0) \?GMtM,
p = 1; 3-Ti'xM
this.p = p; .IYE"0)wJ
} '7E?|B0],
^ 5UIbA(
/** Qb SX'mx<
* 每页记录数量 c5t?S@b
*/ "0]i4d1l
publicint getNum(){ dwmj*+
return num; M VsIyP
} $Itehy
my*/MC^O
/** WJg?R^
* if(num<1) num=1 QU\|RX
*/ ,Z52dggD
publicvoid setNum(int num){ py,z7_Nuh
if(num < 1) evn ]n
num = 1; 5X[=Q>
this.num = num; Y=Bk;%yT=
} HZM&QZHx)`
2>UyA.m0
/** ,rG$JCS'KQ
* 获得总页数 (A?e}M^}
*/ T$RZRZo
publicint getPageNum(){ u/``*=Y@
return(count - 1) / num + 1; 3UBG?%!$f
} 4wK!)Pwq
a|66[
/** }9@,EEhg
* 获得本页的开始编号,为 (p-1)*num+1 mF#{"
*/ &%INfl>o7.
publicint getStart(){ zQD$+q5h
return(p - 1) * num + 1; Rb\\6BU0
} :,:r
` NcWy
/** #:236^xYS
* @return Returns the results. sH#UM(N
*/ Dmn6{jyP
publicList<E> getResults(){ CB6<Vng}C
return results; k+%6:r,r&
} e6]u5;B
r
72Ft?;R
public void setResults(List<E> results){ N0/DPZX7
this.results = results; ?mrG^TV^+r
} /Wk\6
LUJKR6oT{>
public String toString(){ :3u>%
StringBuilder buff = new StringBuilder Ga$+x++'*
/ 1g_Uv;
(); ,LU/xI0O
buff.append("{"); 4Yx?75/
buff.append("count:").append(count); @R>J\>
buff.append(",p:").append(p); a B%DIH,
buff.append(",nump:").append(num); rT5dv3^MW!
buff.append(",results:").append >*dqFZF
t|d9EC]c(
(results); @
Al\:
buff.append("}"); hesL$Z [
return buff.toString(); ,%yjEO
} vA:1z$m
X8p-VCkV
} De\&r~bTW9
Ll%[}C?~]?
$^}?98m