Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [GbrKq(
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~Q=;L>Qd
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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 5@l5exuG*m
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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 s2L]H
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分页支持类: "tl{HM5u
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java代码: Otu?J_ d3
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package com.javaeye.common.util; ;F1y!h67<
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import java.util.List; 28v^j*=*
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publicclass PaginationSupport { RNB-W%
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publicfinalstaticint PAGESIZE = 30; &p#PYs|H
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privateint pageSize = PAGESIZE; dlyGgaV*X
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privateList items; rZ,3:x-:
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privateint totalCount; a
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privateint[] indexes = newint[0]; F
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privateint startIndex = 0; 3KqRw (BK
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public PaginationSupport(List items, int zdem}kBIe
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totalCount){ "E7<S5cr
setPageSize(PAGESIZE); Wk^{Tn/]
setTotalCount(totalCount); B{0]v-w
setItems(items); U}HSL5v
setStartIndex(0); jSBz),.XU}
} {
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public PaginationSupport(List items, int q/w5Dx|:
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totalCount, int startIndex){ 6|Dtx5
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setPageSize(PAGESIZE); 0-OKbw5%=b
setTotalCount(totalCount); CC@U'9]bH
setItems(items); <gX({FA
setStartIndex(startIndex); A/9<} m
} JkR%o
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public PaginationSupport(List items, int S7j(4@
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totalCount, int pageSize, int startIndex){ ox<6qW
setPageSize(pageSize); C:&Sk\
setTotalCount(totalCount); &!;o[joG
setItems(items); >~7XBb08
setStartIndex(startIndex); 3;b)pQ~6CJ
} f3,LX]zKA
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publicList getItems(){ GYy8kp84
return items; 3,Z;J5VL4!
} ,c&t#mu*0
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publicvoid setItems(List items){ B]hRYU
this.items = items; +(`D'5EB(
} s`Z.H5V>\
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publicint getPageSize(){ `"'u
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return pageSize; QgH{J80
} vp&.
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publicvoid setPageSize(int pageSize){ i\Yd_
this.pageSize = pageSize; Q7`)&^
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} @)MG&X
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publicint getTotalCount(){ S_*Gv O
return totalCount; ^^k9Acd~p
} F@z%y'5 Z*
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publicvoid setTotalCount(int totalCount){ |0p@'X1
if(totalCount > 0){ RwK6u-u#9
this.totalCount = totalCount; o=7e8l
int count = totalCount / .|DrXJ\c
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pageSize; qoT&N,/
if(totalCount % pageSize > 0) hX,RuI
count++; 08AD~^^
indexes = newint[count]; 2xi;13?
for(int i = 0; i < count; i++){ 82)=#ye_P
indexes = pageSize * X ?ZLmP7|
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} GXLh(d!C
}else{ uZf
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this.totalCount = 0; ~tL:r=
} B<myt79F_[
} "tOm
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publicint[] getIndexes(){ 1W.oRD&8j/
return indexes; E!WlQr:b$
} F&CvqPI
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publicvoid setIndexes(int[] indexes){ >^W6'Q$P<
this.indexes = indexes; vEG7A$Z"
} c9@3=6S/
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publicint getStartIndex(){ 1Xh@x
return startIndex; st.{AEv@
} (-;(wCEE
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publicvoid setStartIndex(int startIndex){ "`S?q G
if(totalCount <= 0) toj5b;+4F
this.startIndex = 0; vG)B}`M
elseif(startIndex >= totalCount) 04-@c
this.startIndex = indexes jpXbFWgN
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[indexes.length - 1]; VqD_FS;E
elseif(startIndex < 0) 3ohHBo
this.startIndex = 0; $t6t 6<M)
else{ E@Ewx;P5
this.startIndex = indexes !z:j-gT3
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[startIndex / pageSize]; _h,X3P
} #5^OO ou|
} fQ.S ,lMe
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publicint getNextIndex(){ 2cS94h
int nextIndex = getStartIndex() + TZn5s~t
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pageSize; ]
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if(nextIndex >= totalCount) xVI"sBUu
return getStartIndex(); ?#doH,
else ^?q(fK%
return nextIndex; .R4,fCN
} TR
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publicint getPreviousIndex(){ 2h}FotlO
int previousIndex = getStartIndex() - a~!7A
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pageSize; 9)[)07
if(previousIndex < 0) .'l3NV^{
return0; C=K{;.
else 1n*"C!q
return previousIndex; bz,"TG[
} *ni0.
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} ,s}7KE
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抽象业务类 cF iTanu
java代码: <)J@7@!P
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/** 8A*tpMV?J
* Created on 2005-7-12 VsL*&Fk
*/ )$pqe|,
package com.javaeye.common.business; OzH\YN
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import java.io.Serializable; tp ky
import java.util.List; l Ny<E!0
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import org.hibernate.Criteria; xvWP^Qkb
import org.hibernate.HibernateException; #!m^EqF1_
import org.hibernate.Session; *uxKI:rB:
import org.hibernate.criterion.DetachedCriteria; }`2+`w%uZ
import org.hibernate.criterion.Projections; jrm^n_6};
import R(}!gv}s
; d}n89DXj
org.springframework.orm.hibernate3.HibernateCallback; Un+- T
import w8KxEV=
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org.springframework.orm.hibernate3.support.HibernateDaoS `$JOFLa
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upport; or)fx/ %h
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import com.javaeye.common.util.PaginationSupport; Y'}c$*OkI
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public abstract class AbstractManager extends h7xgLe@
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HibernateDaoSupport { HuxvIg
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privateboolean cacheQueries = false; G 8tK"LC
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privateString queryCacheRegion; {=Py|N\\t
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publicvoid setCacheQueries(boolean q #8z%/~k
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cacheQueries){ bDegIW/'w
this.cacheQueries = cacheQueries;
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} XNBzA3W
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publicvoid setQueryCacheRegion(String ?]}=4
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queryCacheRegion){ 5["n] i
this.queryCacheRegion = 0h('@Hb.K#
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queryCacheRegion;
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} E
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publicvoid save(finalObject entity){ 7=A @P
getHibernateTemplate().save(entity); tg ~7^(s
} )_l(WF.
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publicvoid persist(finalObject entity){ eW_EWVH
getHibernateTemplate().save(entity); nxuR^6Ai
} x
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publicvoid update(finalObject entity){ 5YiBPB")
getHibernateTemplate().update(entity); |A H@W#7j
} ?xE'i[F @
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publicvoid delete(finalObject entity){ S2=x,c$
getHibernateTemplate().delete(entity); a7]Z_Gk
} hg `N`O
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publicObject load(finalClass entity, )VG_Y9;Xk:
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finalSerializable id){ w#sP5qKv8
return getHibernateTemplate().load S~ y.>X3"P
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(entity, id); Ap}`Q(.
} _`9WNJiL
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publicObject get(finalClass entity, =mxj2>,&
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finalSerializable id){ "N=q>jaX
return getHibernateTemplate().get tqU8>d0^
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(entity, id); 1| xKb(_l
} OJLyqncw
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publicList findAll(finalClass entity){ ksqb& ux6
return getHibernateTemplate().find("from fp"GdkO#}i
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" + entity.getName()); `u8=~]rblj
} x=1Sbs w{
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publicList findByNamedQuery(finalString Z
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namedQuery){ J]&nZud`
return getHibernateTemplate VmTgD96
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().findByNamedQuery(namedQuery); dQ Ao~]B
} M[&p[P@
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publicList findByNamedQuery(finalString query, Nbm$ta
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finalObject parameter){ 3>^S6h}o
return getHibernateTemplate l{3ZN"`I
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().findByNamedQuery(query, parameter); l @r`NFWD@
} RgVg~?A@
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publicList findByNamedQuery(finalString query, ?? Dv\yLZI
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finalObject[] parameters){ 8j@ADfZ9
return getHibernateTemplate GF*E+/
;
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().findByNamedQuery(query, parameters); `?vI_>md'!
} '\LU 8VC
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publicList find(finalString query){ 2ZQ|nwb7
return getHibernateTemplate().find {
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(query); JU-eoB}m
} bg,VK1
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publicList find(finalString query, finalObject 8EZ,hY^
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parameter){ vP/sG5$x
return getHibernateTemplate().find ; DI"9
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(query, parameter); ev(E
} z~yLc{M
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public PaginationSupport findPageByCriteria (FNX>2Mv
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(final DetachedCriteria detachedCriteria){ X#u< 3<P
return findPageByCriteria 2H`;?#Uq:
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Z4PAdT
} g+u5u\k
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public PaginationSupport findPageByCriteria O:[@?l
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(final DetachedCriteria detachedCriteria, finalint 3+:uV
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startIndex){ =D?{d{JT
return findPageByCriteria HlX 2:\\
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(detachedCriteria, PaginationSupport.PAGESIZE, 7o`pNcabtz
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startIndex); o(Ro/U(Wu
} Sy34doAZ
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public PaginationSupport findPageByCriteria LfG$?<}hR
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(final DetachedCriteria detachedCriteria, finalint ~2?UEv6
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pageSize, /)xQ# yfX
finalint startIndex){ 0:k
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return(PaginationSupport) 0XrOOYmx
))#_@CwRr
getHibernateTemplate().execute(new HibernateCallback(){ BjbpRQ,
publicObject doInHibernate '3ZYoA%
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(Session session)throws HibernateException { :X-\!w\
Criteria criteria = <=!|U0YV
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detachedCriteria.getExecutableCriteria(session); Q02:qn?T
int totalCount = PhC{Gg
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((Integer) criteria.setProjection(Projections.rowCount 08E ,U
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()).uniqueResult()).intValue(); {c:ef@'U
criteria.setProjection h5m6 )0"
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(null); +N!!Z2
List items = %p.hwgvnp
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criteria.setFirstResult(startIndex).setMaxResults uB uwE6
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(pageSize).list(); qy~@cPT
PaginationSupport ps = 9mH+Ol#(
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new PaginationSupport(items, totalCount, pageSize, +\`t@Ht#
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startIndex); t%>x}b"2T
return ps; {:d9q
} o[CjRQY]P
}, true); I~I$/j]e`
} O\qY?)
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public List findAllByCriteria(final vH9Gf
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DetachedCriteria detachedCriteria){ wKs-<b%;
return(List) getHibernateTemplate Yo#F ;s7
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().execute(new HibernateCallback(){ |{@_J
publicObject doInHibernate -)ag9{ *
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(Session session)throws HibernateException { SB` "%6
Criteria criteria = " ^:$7~%bA
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detachedCriteria.getExecutableCriteria(session); lEv<n6:_
return criteria.list(); wC[Bh^]
} hFWK^]~ a
}, true); ;P4tqY@
} ym)`<[T
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public int getCountByCriteria(final
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DetachedCriteria detachedCriteria){ C]+T5W\"<B
Integer count = (Integer) mh8~w~/[
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getHibernateTemplate().execute(new HibernateCallback(){ We*)RXm%
publicObject doInHibernate n/]$k4h
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(Session session)throws HibernateException { ~_Mz05J-\_
Criteria criteria = :-kXZe
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detachedCriteria.getExecutableCriteria(session); f@a@R$y
return R9z^=QKcH
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criteria.setProjection(Projections.rowCount |+MV%QG;
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()).uniqueResult(); ZXj;ymC'
} Tse
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}, true); Wd_cNR\
return count.intValue(); %Sdzr!I7*
} O/=i'0Xv
} kDG'5X;+
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用户在web层构造查询条件detachedCriteria,和可选的 /U%Xs}A)
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 sm>Hkci%
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PaginationSupport的实例ps。 JDzkv%E^
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ps.getItems()得到已分页好的结果集 *?+maK{5+
ps.getIndexes()得到分页索引的数组 Y(]&j`%
ps.getTotalCount()得到总结果数 ,1YnWy*
ps.getStartIndex()当前分页索引 1!E+(Iq
ps.getNextIndex()下一页索引 k+S 6)BQ7U
ps.getPreviousIndex()上一页索引 &,Xs=Lvmq
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /N
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 a]465FY
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一下代码重构了。 gi7As$+E
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我把原本我的做法也提供出来供大家讨论吧: M,Px.@tw.
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首先,为了实现分页查询,我封装了一个Page类: |^ml|cb
java代码: zSYWNmj&
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/*Created on 2005-4-14*/ t
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package org.flyware.util.page; x=qACoq
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/** 15r<n
* @author Joa `
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* Iy](?b
*/ E$FXs~a
publicclass Page { `oh'rm3'8
-NVk>ENL4
/** imply if the page has previous page */ T!hU37g h?
privateboolean hasPrePage; 2f]9I1{
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/** imply if the page has next page */ Wv"[,5
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privateboolean hasNextPage; 4.3Bz1p
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/** the number of every page */ VPf*>ph=
privateint everyPage; (o\:rLZu
'7W?VipU
/** the total page number */ fwI Zr~l
privateint totalPage; U3^T.i"R
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/** the number of current page */ Y:VM5r)
privateint currentPage; I/GZ
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/** the begin index of the records by the current C/[2?[
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query */ dox QS ohS
privateint beginIndex; "$#x+|PyC
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f$k#\=2%
/** The default constructor */ )4a&OlEI
public Page(){ CPGXwM=
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} yi7-[W}
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/** construct the page by everyPage 3;j?i<kM
* @param everyPage }_M.-Xm
* */ %.b)%=
public Page(int everyPage){ ;=Bf&hY&
this.everyPage = everyPage; -Tk~c1I#`
} ha'oLm#
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/** The whole constructor */ Gz!72H
public Page(boolean hasPrePage, boolean hasNextPage, -^;G^Uq6=
)j@k[}R#g
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int everyPage, int totalPage, -b(:kAwStk
int currentPage, int beginIndex){ [/*854
this.hasPrePage = hasPrePage; |n=kYs
this.hasNextPage = hasNextPage; q!<`ci,uS
this.everyPage = everyPage; {:Z# 8dGe
this.totalPage = totalPage; S]1+tj
this.currentPage = currentPage; [8SW0wsk
this.beginIndex = beginIndex; cCU'~
} OR( )D~:n
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/** r[M]2h
* @return GA6Z{U{XS
* Returns the beginIndex. tB[(o%k
*/ d+ih]?
publicint getBeginIndex(){ ,q/K&'0`
return beginIndex; ,US~p_M!
} "~7| !9<
*=S\jek
/** 4^alAq^
* @param beginIndex PKfxL}:"8
* The beginIndex to set. =o _d2Ak
*/ ^=D77 jS
publicvoid setBeginIndex(int beginIndex){ _ZD)#?
this.beginIndex = beginIndex; +B_q? 6pR
} Roy`HU
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/** ui7 0|
* @return nUhD41GJ
* Returns the currentPage. -j]r\EVKS
*/ |RAi6;
publicint getCurrentPage(){ yi# Nrc5B
return currentPage; `-s+ zG
} R`ZU'|
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/** =t&B8+6
* @param currentPage *xU^e`P
* The currentPage to set. mbd
*/ v2EM| Q xp
publicvoid setCurrentPage(int currentPage){ w>H!H6Q
this.currentPage = currentPage; \fU{$
} x7Ly,
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/** A>OL5TCl
* @return w*#k&N[X
* Returns the everyPage. WqY:XE+?\
*/ ;csAhkf:S
publicint getEveryPage(){ xYM/{[
return everyPage; ^lRXc.c z
} A~I}[O~(pb
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/** ]v94U b
* @param everyPage ID'@}69.S
* The everyPage to set. !&E>8h
*/ w6R=r
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publicvoid setEveryPage(int everyPage){ DWk'6;e4j
this.everyPage = everyPage; {E6b/G?Q
} 9eGM6qW\_
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/** xfO!v>
* @return A[ /0on5r
* Returns the hasNextPage. '4dnC2a]
*/ $hndb+6q
publicboolean getHasNextPage(){ HQ@X"y
n
return hasNextPage; gl.P#7X
} 2d<ma*2n(
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]
/** N;-+)=M,rf
* @param hasNextPage t}nZrD
* The hasNextPage to set. IH[/fd0
*/ r]BB$^@@V
publicvoid setHasNextPage(boolean hasNextPage){ :;{U2q+
this.hasNextPage = hasNextPage; qdZn9i
} 4^70r9hV9
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/** .yi.GRk
* @return xE;fM\7pu
* Returns the hasPrePage. o0s+ roiD
*/ LL9Mty,
publicboolean getHasPrePage(){ ]wa?~;1^&
return hasPrePage; MV9{>xX
} Jev@IORN\
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/** \^N9Q9{7]
* @param hasPrePage \+Qx}bS{
* The hasPrePage to set. j*W]^uT,
*/ 5>}L3r>a;
publicvoid setHasPrePage(boolean hasPrePage){ {U^mL6=&v
this.hasPrePage = hasPrePage; <diI*H<G
} 1#]tCi`
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/** 4y
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* @return Returns the totalPage. dHf_&X2A
* /d'^XYOC
*/ 4X#>;
publicint getTotalPage(){ @YpA'cX7
return totalPage; =,gss&J!!
} _Mq@58q'
.HZYSY:X
/** E# e=<R
* @param totalPage ,E)bS7W
* The totalPage to set. &giJO-^
f
*/ vhWj_\m
publicvoid setTotalPage(int totalPage){ I+`~6
this.totalPage = totalPage; ms;Lu-UR
} 4"l(rg
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} I \vu?$w
kz,Nz09}W
Sm+Ek@Ax
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Y&'2/zI6~
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一
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个PageUtil,负责对Page对象进行构造: xiA9X]FB
java代码: _6=6 b!hD
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/*Created on 2005-4-14*/ 0qJ(3N
package org.flyware.util.page; bG.aV#$FIg
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import org.apache.commons.logging.Log; <-}6X
import org.apache.commons.logging.LogFactory; wQM(Lm#Q
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/** YroKC+4"i
* @author Joa ix7N q7!N
* &)xoR4!2
*/ +` Em&
publicclass PageUtil { ub,Sj{Mq"
wG^{Jf&@$
privatestaticfinal Log logger = LogFactory.getLog 5"XcVH4g
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(PageUtil.class); IWm|6@y
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/** 7|,5;
* Use the origin page to create a new page InPq1AH
* @param page UnW,|n8
* @param totalRecords R['qBHQ?
* @return +(cs,?`\
*/ TmzEZ<} &7
publicstatic Page createPage(Page page, int
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totalRecords){ ,a5I:V^\
return createPage(page.getEveryPage(), WNd(X}
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page.getCurrentPage(), totalRecords); DJrA@hm/Y
} s'} oVx]
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/** `n5)oU2q
* the basic page utils not including exception !n)2HDYhx,
"'6KQnpZ
handler O$#`he/jm
* @param everyPage ajkRL|^
* @param currentPage ~5cLI;4h
* @param totalRecords =C<_rBY
* @return page tgg*6lc
*/ gfih;i.pY
publicstatic Page createPage(int everyPage, int s\>$ K%!H?
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currentPage, int totalRecords){ c1MALgK~}\
everyPage = getEveryPage(everyPage); #{ `(;83
currentPage = getCurrentPage(currentPage); Nv #vfh9}P
int beginIndex = getBeginIndex(everyPage, EVRg/{X
kCN9`9XI{
currentPage); \!G&:<h
int totalPage = getTotalPage(everyPage, @Cw<wrem
,pf<"^li
totalRecords); &:'Uh
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boolean hasNextPage = hasNextPage(currentPage, 8b|&
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totalPage); #W!@j"8eK
boolean hasPrePage = hasPrePage(currentPage); ,/o<O jR
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returnnew Page(hasPrePage, hasNextPage, ZIpL4y
=_
everyPage, totalPage, H$1R\rE`
currentPage, lm]4zs /A
MK~viSgi
beginIndex); /p X\)wi
} b.C!4^
c5]^jUB6
privatestaticint getEveryPage(int everyPage){ aSKI%<?xN
return everyPage == 0 ? 10 : everyPage; mNcTO0p&
} Jqjb@'i
XY0Gjo0
privatestaticint getCurrentPage(int currentPage){ $]xe,}*Af
return currentPage == 0 ? 1 : currentPage; MH!'g7iK8
} d;;]+%
R2t5T-8`c
privatestaticint getBeginIndex(int everyPage, int #Du1(R
7c4\'dt#
currentPage){ z#bOFVg#
return(currentPage - 1) * everyPage; ho fZpM
} 9:YiLoz?
mpXco *!_
privatestaticint getTotalPage(int everyPage, int Ay2Vz>{
Tfs7SC8ta
totalRecords){ pS*vwYA
int totalPage = 0; >RF[0s'-
$S=lm {
if(totalRecords % everyPage == 0) [T~O%ly7x&
totalPage = totalRecords / everyPage; 2x3&o|J
else p# O%<S@?
totalPage = totalRecords / everyPage + 1 ; H4^-M Sw
X^fMt]
return totalPage; }MXZ
} yv4hH4Io
ldi'@^
privatestaticboolean hasPrePage(int currentPage){ y=5s~7]
return currentPage == 1 ? false : true; ;se-IDN
} uK}k]x\z
duT2:~H2
privatestaticboolean hasNextPage(int currentPage, ihf5`mk/$
3EF|1B/5
int totalPage){ :4&qASn
return currentPage == totalPage || totalPage == xJN
JvA
]W-:-.prh
0 ? false : true; Z"% =
} s 6vsV
KuE
2a,E4
'UW7zL5
} V A4_>6
C37KvLQ
fLct!H3
f=g/_R2$xN
^<[oKi;>
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ZDcv-6C)B
4TC
!P}
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 b\dBt#mB!
Qighvei
做法如下: m0XK?;\V
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 B.Ic8'
VX2bC(E'%
的信息,和一个结果集List: vr=iG
xD
java代码: 7GWPsaPn
IkL|bV3E0
552c4h/T
/*Created on 2005-6-13*/ EJb"/oLla
package com.adt.bo; "A,]y E
tlI3jrgw
import java.util.List; G5bi,^G7
qmtVk
import org.flyware.util.page.Page; C&Ow*~
[1 w
/** YeYFPi#
* @author Joa 8O("o7~"
*/ HQ ^> ~
publicclass Result { }4
P@`>e/`
IEjKI"
private Page page; n=L;(jp<j
+cQ4u4
private List content; u5$\E]+_
q8P| ]
/** =ni&*&
* The default constructor >umcpkp-h
*/ lmQ!q>N
public Result(){
VG q'
super(); y<8)mw
} R%8nR6iG"
9I+;waLlB
/** YJ.'Yc
* The constructor using fields #B;` T[
* -"<H$
* @param page ATk>:^n
* @param content `c(,_oa{
*/ .e"De-u
public Result(Page page, List content){ o/2\8
this.page = page; `f8{^Rau
this.content = content; 6./h0kD`
} ShF
][v1L
vA;ml$
/** !ck=\3pr
* @return Returns the content. $9M>B<]
*/ 8/ZJkI
publicList getContent(){ leg@ia
return content; TW:vL~L
} k2,n:7
V.: a6>]
/** = 14'R4:
* @return Returns the page. ]J5[ZVz
*/ it D%sKo
public Page getPage(){ `i,ZwnLh{
return page; %4imlP
} ORp6
ZgZ}^x
/** ]cLpLA"
* @param content Tf21K9+`L
* The content to set. )p(5$AR7
*/ zPH1{|H+l
public void setContent(List content){ uy~5!i&
this.content = content; @@'zMV%
} wvp\'* $
hc`9Y
/** !|}J{
* @param page A5F< <
* The page to set. lWd)(9Kj
*/ =}Bq"m
publicvoid setPage(Page page){ 7.hVbjy'-
this.page = page; S%kE<M?
} #HJ F==
} ~;Ss)d
Xi4!7IOmo
f?2Y np=@
!b7]n-1zs
` {k>I^Pg
2. 编写业务逻辑接口,并实现它(UserManager, D3HE~zkI
"z=A=~~<{
UserManagerImpl) [o*u!2 r
java代码: D$YAi%*H
HC?yodp^
h34|v=8d
/*Created on 2005-7-15*/ /-8v]nRB
package com.adt.service; |t4k&Dkx`
A\i/@x5#
import net.sf.hibernate.HibernateException; E`=y9r*Z
gt';_
import org.flyware.util.page.Page; }Xrs"u,
`(_cR@\
import com.adt.bo.Result; vD[@cm
*jTr
/** #CW]70H`
* @author Joa eW1$;.^
*/ {5#P1jlT
publicinterface UserManager { dY;^JPT
`[jQn;
public Result listUser(Page page)throws dV<M$+;s]
InH
R>,
HibernateException; cx_[Y
=c(_$|0
} 4CW/
oZA|IF8U0
A0V"5syY
wkdd&Nw;
F$ZWQ9&5U0
java代码: PxfeU2^{0
SL hki)|
p<Ah50!B
/*Created on 2005-7-15*/ p27A#Uu2}
package com.adt.service.impl; i74^J +xk
m{JiF-=u
import java.util.List; Bag2sk
e%R+IH5i
import net.sf.hibernate.HibernateException; f`:e#x
prlB9,3|C
import org.flyware.util.page.Page; &M6)-V4
import org.flyware.util.page.PageUtil; /raM\EyrlP
= EyxM
import com.adt.bo.Result; 1_fFbb"
import com.adt.dao.UserDAO; ngsax1xO
import com.adt.exception.ObjectNotFoundException; it&c
,+8
import com.adt.service.UserManager; Wey-nsk
e&OMW,7
/** _-%ay
* @author Joa lE?e1mz{
*/ Jj fNH
~
publicclass UserManagerImpl implements UserManager { T9t9])
q[M7)-
private UserDAO userDAO; @7u4v%,wB
;wL*
/** Te[[xhTyw
* @param userDAO The userDAO to set. j /)cdP
*/ pEH[fA]
publicvoid setUserDAO(UserDAO userDAO){ >u*woNw(XM
this.userDAO = userDAO; d=oOMXYa
} I%e7:cs >
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+
/* (non-Javadoc) ~_8Ve\Y^ /
* @see com.adt.service.UserManager#listUser B
0 K2Uw
at,Xad\j
(org.flyware.util.page.Page) tPO.^
*/ ?9H7Twi+T
public Result listUser(Page page)throws **_VNDK+
iJ?8)}
HibernateException, ObjectNotFoundException { Q,#M
0
int totalRecords = userDAO.getUserCount(); 'x+0
yd
if(totalRecords == 0) 2}$Vi$
R
throw new ObjectNotFoundException }td+F&l($V
UM|GX
("userNotExist"); >B8)Wb:
page = PageUtil.createPage(page, totalRecords); jph~g*Z
List users = userDAO.getUserByPage(page); AN^ ,
returnnew Result(page, users); AA>5h<NM
} Wn0r[h5t
<Ks?g=K-
} eb9qg.9Z
n 8AND0a1C
u%XFFt5
*9j9=N?
*uA?}XEfi
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <e/O"6='Z
AU87cqq
询,接下来编写UserDAO的代码: GVn9=[r
3. UserDAO 和 UserDAOImpl: Y0s^9?*
java代码: 1Y}gki^F
"Y(S G
R^1= :<)C
/*Created on 2005-7-15*/ OiM{@
package com.adt.dao; ;2L=WR%
q hK;#<#
import java.util.List; ^z[s;:-
\RQ5$!O
import org.flyware.util.page.Page; .8b4
Cf`UMQ a
import net.sf.hibernate.HibernateException; \M>AN
Z}
Q.z2 (&
/** }[LK/@h
* @author Joa 3q pkMu3
*/ _JR4
PKtx
publicinterface UserDAO extends BaseDAO { hZ2PP ^
7MoO2
publicList getUserByName(String name)throws +QldZba
{H])Fob
HibernateException; PDD` eK}Fj
*k+QX
publicint getUserCount()throws HibernateException; A:
0]
n
+% U@
publicList getUserByPage(Page page)throws U}gYZi;;$
JiI(?I
HibernateException; ?MpGzCPa
Q=^}B}G
} p-*BB_J"
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`&pb`P<`
_F@FcFG1Z*
HowlJ[ km%
java代码: F6%rH$aS
1"v;w!uh
1d\K{ 7i#
/*Created on 2005-7-15*/ }}_WZ},h
package com.adt.dao.impl; B5I(ai7<M
K9w24Oka
import java.util.List; Z: Kob
b
zEO
9TuBO
import org.flyware.util.page.Page; Ho\+xX
//wmJ |
import net.sf.hibernate.HibernateException; ( _nkscf
import net.sf.hibernate.Query; TS
UN(_XGW
>@oO7<WB
import com.adt.dao.UserDAO; OVj,qL)
9 z3Iwl
/** j<l>+.,
U
* @author Joa E> 4
\9
*/ )$th${pd#v
public class UserDAOImpl extends BaseDAOHibernateImpl Uj!L:u2b
4
Qw;r
implements UserDAO { @&EP&
$*
$7BD~U
/* (non-Javadoc) X(WG:FP27
* @see com.adt.dao.UserDAO#getUserByName %H}+'.8
!0fK*qIL
(java.lang.String) \[D"W{9l
*/ Q45rP4mQ
publicList getUserByName(String name)throws Pv0+`>):
pn
=S%Qf]
HibernateException { pAa{,,Qc
String querySentence = "FROM user in class \{UiGCK
0f-gQD
com.adt.po.User WHERE user.name=:name"; E*
lqC h
Query query = getSession().createQuery @l;f';+
O]~p)E
(querySentence); c69C=WQ
query.setParameter("name", name); ~z< ? Wh
return query.list(); SnXYq7`t
} F[ ? t"d
DH9?~|
/* (non-Javadoc) KRXe\Sx
* @see com.adt.dao.UserDAO#getUserCount() g8qN+Gg
*/ l7x%G@1#~W
publicint getUserCount()throws HibernateException { qY0Ic5wCY
int count = 0; eA+6-'qN
String querySentence = "SELECT count(*) FROM 0&mz'xra
Zmp ^!|=X!
user in class com.adt.po.User"; 5|>jz `
Query query = getSession().createQuery >5 i8%r
5k\61(*s
(querySentence); kw yvd`J8
count = ((Integer)query.iterate().next ^T<<F}@q
#K4wO!d
()).intValue(); 6'Lij&,f?{
return count; 3gGF?0o
} IzL
yn
TnKe"TA|9
/* (non-Javadoc) ZM)a4h,kcm
* @see com.adt.dao.UserDAO#getUserByPage TI*uNS;-
UnO -?
(org.flyware.util.page.Page) a]ftE\99
*/ Y)!5Z.K
publicList getUserByPage(Page page)throws "C0oFRk
-bs~{
HibernateException { qQ|v~^
String querySentence = "FROM user in class CF$^we
zb9$
com.adt.po.User"; 7%?A0%>6G
Query query = getSession().createQuery yt<K!=7&
^ 5UIbA(
(querySentence); Qb SX'mx<
query.setFirstResult(page.getBeginIndex()) c5t?S@b
.setMaxResults(page.getEveryPage()); "0]i4d1l
return query.list(); K(Cv9YQ
} /[us;=CM
*.i`hfRc
} nNL9B~d
WJg?R^
QU\|RX
,Z52dggD
py,z7_Nuh
至此,一个完整的分页程序完成。前台的只需要调用 JM!o(zbt
U`:$1*(`
userManager.listUser(page)即可得到一个Page对象和结果集对象 \6sp"KqP
eR;cl$
的综合体,而传入的参数page对象则可以由前台传入,如果用 RE*SdazY?
#^eviF8
webwork,甚至可以直接在配置文件中指定。 Dpof~o,f
T"dEa-O
下面给出一个webwork调用示例: paiF ah
java代码: km8[azB o
+='.uc_
j[c|np4k\
/*Created on 2005-6-17*/ ;up89a-,9
package com.adt.action.user; @y}1%{,%
h"q`gj
import java.util.List; ymzlRs1^Ct
N.3M~0M*
import org.apache.commons.logging.Log; }9@,EEhg
import org.apache.commons.logging.LogFactory; }t]CDa_n
import org.flyware.util.page.Page; oU{m\r
2AU_<Hr6
import com.adt.bo.Result; ^S[Mg6J
import com.adt.service.UserService; PiM@iS
import com.opensymphony.xwork.Action; r0hu?3u1?
xy[R9_V
/** #,$d!l @
* @author Joa jtN2%w;
*/ RELLQpz3
publicclass ListUser implementsAction{ ]X{LZYk
!R4`ihi1
privatestaticfinal Log logger = LogFactory.getLog &{"aD&
;JDxl-~
(ListUser.class); MT|}[|_
gwT"o
private UserService userService; uE+]]ir
Cg-khRgLS
private Page page; friNo^v&
ci|6SaY*
privateList users; M"5,8Q`PkI
+MXI;k_
/* _kgw+NA&-H
* (non-Javadoc) wD"Y1?Mr
* \~U8<z
* @see com.opensymphony.xwork.Action#execute() JZN'U<R
*/ 41,Mt
publicString execute()throwsException{ \u2p] K>
Result result = userService.listUser(page); p)Z$q2L
page = result.getPage(); g)2}`}
users = result.getContent(); =3l%ZL/
return SUCCESS; "M1[@xog
} @/XA*9]l
F}.<x5I-;h
/** $^d,>hJi
* @return Returns the page. I=|b3-
*/ tecCU[O
public Page getPage(){ (|"KsGl
return page; b`fPP{mG
} d\D.l^
^q7
fN0"6
/** &+d>xy\^/
* @return Returns the users. M-"%4^8_
*/ jBarY g
publicList getUsers(){ ,;hIyT
return users; 6:#zlKYJ
} i4&"-ujrm
G2zfdgW${/
/** @9-z8PyF
* @param page !A, ]
* The page to set. X^eTf-*T
*/ | Fm(
publicvoid setPage(Page page){ uI!rJc>TX
this.page = page; PW~+=,
} V8 }yK$4b
[n44;
/** xP
"7B9B
* @param users >@rsh-Z
* The users to set. c54oQ1Q&"
*/ j0~]o})@i
publicvoid setUsers(List users){ O4S~JE3o
this.users = users; 7q^osOj"
} y08.R.
l
|Xlpgdiu
/** 4(f[Z9 iZ]
* @param userService B{PI&a9~s%
* The userService to set. M6[&od
*/ &2d^=fih
publicvoid setUserService(UserService userService){ nK)U.SZ
this.userService = userService; `rN,*kcP
} I>B-[QEC
} 4U*J{''L
Om,+59ua*
Q
&<:W4N*
540-l Me
d dkh*[
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 67wY_\m 9I
?<STt 9
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 4#1[i|:M
MuQyHEDF
么只需要: uckag/tv
java代码: yF8 av=<{
3pl/kT.\
P4-`<i]!S
<?xml version="1.0"?> q;3.pRw(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork N0,wT6.
BxS\"W
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ]Nz~4ebB
MkEr|w'
1.0.dtd"> %QCh#v=ks
@`^+XP K\
<xwork> xT6&;,|`
wt0^R<28
<package name="user" extends="webwork- B"ZW.jMaI
L<'3O),}
interceptors"> *NHBwXg+
;P3sDN
<!-- The default interceptor stack name jCa%(2~iQ7
!o1{. V9q
--> =UE/GTbl
<default-interceptor-ref
G?AZ%Yx
ze@NqCF
name="myDefaultWebStack"/> (A|Gb2 X
DK;p6_tT
<action name="listUser" D~E1hr&Vd>
a|Io)Qhr
class="com.adt.action.user.ListUser"> eKPxSN Z
<param z-$ bce9*
XkLl (uyh
name="page.everyPage">10</param> kscZ
zXv
<result G0Q}
1
KHV5V3q4
name="success">/user/user_list.jsp</result> KCu @5`p
</action> =NMT H[
y!)
</package> rf^Q%ds
xOnbYU
</xwork> |WqEJ*$,
%{WZ
V3DXoRE-8i
Ir'(GB
D/uGL
t~D(
v10p]=HmO
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 ()a(PvEO
m7}PJ^*b
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。 <ZGEmQ
mN
Hd
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 v6(Yz[
&'4{/Gz
W/q-^Zkt,9
<+I^K 7
Z]kk.@P
我写的一个用于分页的类,用了泛型了,hoho 2[6>h)
ky>0
java代码: 3NAU|//J
_ZX"gHx
__o`+ ^FS
package com.intokr.util; ]wFKXZeK
?@8[1$1a
import java.util.List; .@KpN*`KH
hqrI%%
/** C%_^0#8-0
* 用于分页的类<br> Ww-%s9N<
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #2l6'gWE0
* Fb#.Gg9b>
* @version 0.01 hiO:VA
* @author cheng A`_(L|~
*/ kzU;24"K
public class Paginator<E> { xEdCGwgp#
privateint count = 0; // 总记录数 `7_=2C
privateint p = 1; // 页编号 DID&fj9m
privateint num = 20; // 每页的记录数 swNJ\m
privateList<E> results = null; // 结果 9DcUx-
3yg22y&l
/** O92a*)
* 结果总数 jm9J-%?
*/ ]AkHNgW
publicint getCount(){ 7xz~%xC.
return count; 9QE|p
} #vh1QV!Ho
#!V
[(/
publicvoid setCount(int count){ Dlz||==
this.count = count; :aHD'K
} 'D#iT}Vu
eLE9-K+
/** DE"KbA0}
* 本结果所在的页码,从1开始 EXn$ [K;
* Y8!T4dkn
* @return Returns the pageNo. L(tS]yWHw
*/ \|^fG9M~
publicint getP(){ %~%1Is`4J
return p; y\0<f `v6
} w20E]4"
`.>5H\w0e
/** Fq3[/'M^
* if(p<=0) p=1 wUkLe-n,dE
* 3?|gBiX
* @param p E><!Owxt/
*/ 2B&Yw
publicvoid setP(int p){ .s$#: ls?
if(p <= 0) ^,S\-Uy9
p = 1; d.y2`wT
this.p = p; DCS$d1
} ]}z;!D>
:(tSL{FO
/** 2}`Q9?
* 每页记录数量 jRIjFn|~{Y
*/ pl62mp!
publicint getNum(){ [XFZ2'OO
return num; 1o)Vzv
} SR>Sq2cW0
.gUceXWH3
/** z{T2!w~[
* if(num<1) num=1 G"!YV#"~
*/ x" 21 Jh
publicvoid setNum(int num){ ~/?JRL=
if(num < 1) |F5^mpU
num = 1; L8-
this.num = num; _nu
%`?Va
} N!6{c~^
pAg;Rib
/** *0bbSw1kc
* 获得总页数 "aNl2 T
*/ `K[:<p}
publicint getPageNum(){ tm\ <w H
return(count - 1) / num + 1; wqDRFZ1*P
} ^9T6Ix{=
EFeG[bxM
/** !NuYx9L?L
* 获得本页的开始编号,为 (p-1)*num+1 -x
)(2|
*/ pGw|T~e%
publicint getStart(){ {#M=gDhbX
return(p - 1) * num + 1; u:H@]z(x
} ]RHR> =;
PHRc*G{
/** X'N4a
* @return Returns the results. Yjz'lWg
*/ wd*i&ooQ*L
publicList<E> getResults(){ -k\7k2
return results; )f#@`lf[<
} Y{y #us1
^EU&6M2
public void setResults(List<E> results){ =!NYvwg6;o
this.results = results; I%xrDiK97
} }i_[wq{E&
lv9Ss-c4
public String toString(){ u#=Yv|9
StringBuilder buff = new StringBuilder HN>eS Y+
%Fb"&F^7
(); oQ!} @CaN|
buff.append("{"); J)(H-xvV
buff.append("count:").append(count); 2^Gl;3
buff.append(",p:").append(p); +T[3wL~
buff.append(",nump:").append(num); @t`|w.]ml
buff.append(",results:").append nut;ohIh
G 8|[.n
(results); AG)N^yd
buff.append("}"); [:$j<}UmB
return buff.toString(); /b@0HL?
} >K#Z]k
Vja' :i
} FVLXq0<Cj
L]0+u\(
IDBhhv3ak