Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 S r#fyr
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ivgwm6M
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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 =*)O80oaW
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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 HDXjH|of
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。 :92a34
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分页支持类: #L*@~M^]
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java代码: KL_}:O68
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package com.javaeye.common.util; x`|tT%q@l
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import java.util.List; u C8T!z
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publicclass PaginationSupport { W&re;?Z{ke
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publicfinalstaticint PAGESIZE = 30; X72X:"
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privateint pageSize = PAGESIZE; DDCQ Af
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privateList items; 8LM1oal}
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privateint totalCount; Oj|p`Dzh
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privateint[] indexes = newint[0]; CzsY=DBH=
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privateint startIndex = 0; !?-5hh1\
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public PaginationSupport(List items, int DO,&Foh\
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totalCount){ >mDubP
setPageSize(PAGESIZE); s/&]gj"
setTotalCount(totalCount); ob5nk^y
setItems(items); I!0+RP(
setStartIndex(0); GpQF* x
} EYD{8Fw-
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public PaginationSupport(List items, int ZJ}LnPr
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totalCount, int startIndex){ D\&y(=fzf
setPageSize(PAGESIZE); N'BctKL
setTotalCount(totalCount); T-8nUo}i
setItems(items); HnY"6gTNK
setStartIndex(startIndex); ^3s&90
} `Q^Sm`R
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public PaginationSupport(List items, int M4PUJZ]
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totalCount, int pageSize, int startIndex){ Q3{&'|}^2
setPageSize(pageSize); e(% Solkm?
setTotalCount(totalCount); 1Moh`
setItems(items); o-Fle, qf
setStartIndex(startIndex); xi^e =:;`
} BiCa "
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publicList getItems(){ oi4Wxcj
return items; _Vf|F
} 0!\q
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publicvoid setItems(List items){ ^aWNtY'
:
this.items = items; nL20}"$E
} O;t?@!_
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publicint getPageSize(){ ~*]`XL.-
return pageSize; 0lh6b3tdP
} yC*B OJS
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publicvoid setPageSize(int pageSize){ U+M?<4J)"
this.pageSize = pageSize; cyeDZ)
} 0\^2HjsJ
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publicint getTotalCount(){ sBI%lrO
return totalCount; !T(Omve)
} "(VcYQ+
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publicvoid setTotalCount(int totalCount){ 7f,WzvV
if(totalCount > 0){ zm"g,\.d
this.totalCount = totalCount; <]qd9mj5
int count = totalCount / tX}S[jdq
DA@hf
pageSize; *9wHH-#
if(totalCount % pageSize > 0) U {!{5l:
count++; ^}\R]})w"
indexes = newint[count]; ]arskmB]
for(int i = 0; i < count; i++){ s4k%ty}
indexes = pageSize * fG5} '8
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i; X6
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} #;]F:TlR
}else{ 0 d]G
this.totalCount = 0; ^ w1R"qE"m
} 2` qXDfD`
} 0Ch._~Q+20
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publicint[] getIndexes(){ gP%!
return indexes; @!O{>`
} Z"T(8>c;g
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publicvoid setIndexes(int[] indexes){ 7E)7sd
this.indexes = indexes; a[ l5k
} mj|9x1U)
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publicint getStartIndex(){ X+@,vCC
return startIndex; ^`?>
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} HE'8
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publicvoid setStartIndex(int startIndex){ XjU; oh4:.
if(totalCount <= 0) 1]`HX=cl
this.startIndex = 0; /MtacR
elseif(startIndex >= totalCount) ^SCWT\E
this.startIndex = indexes )zV5KC{{
9%6`ZS~3
[indexes.length - 1]; X
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elseif(startIndex < 0) Q6>( Z
this.startIndex = 0; 5Vqvb|
else{ HpAZ{P7
this.startIndex = indexes x0GZ2*vfsb
bf(&N-"A
[startIndex / pageSize]; tYa8I/HpT
} Ts6X:D4,
} V1;-5L75
AFED YRX
publicint getNextIndex(){ RfRaWbn
int nextIndex = getStartIndex() + &N ;6G`3
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pageSize; 4iW2hV@m
if(nextIndex >= totalCount) fh<G&E8
p
return getStartIndex(); bnQO}G
else .5xg;Qg\Y
return nextIndex; =1capix 1r
} $0t
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publicint getPreviousIndex(){ ~!kbB4`WK
int previousIndex = getStartIndex() - !6C d.fpWL
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pageSize; zY-m]7Yf
if(previousIndex < 0) sA.yb,Fw
return0; ZeZwzH)BD
else =T]OYk
return previousIndex; p<e~x/@m*
} bP@_4Dy
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} V
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抽象业务类 6 -}gqkR
java代码: *93 N0m4Rl
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/** "Wp<^s sMo
* Created on 2005-7-12 Le!I-i(aD
*/ `fyAV@X
package com.javaeye.common.business; :ux`*,zh
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import java.io.Serializable; 2Mda'T8
import java.util.List; $Vzfhj-if
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import org.hibernate.Criteria; %ZK}y{u\
import org.hibernate.HibernateException; =qRVKz
import org.hibernate.Session; P'8E8_M}
import org.hibernate.criterion.DetachedCriteria; Apn#o2
import org.hibernate.criterion.Projections; Jk*MxlA.b
import -E7\.K3
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org.springframework.orm.hibernate3.HibernateCallback; KX`,7-
import e
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org.springframework.orm.hibernate3.support.HibernateDaoS jo~Pr
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upport; ks}o9[D3
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import com.javaeye.common.util.PaginationSupport; 5hAg*zJb5o
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public abstract class AbstractManager extends ?x@khzk
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HibernateDaoSupport { G.}yNjL8
@w0[5ZAj
privateboolean cacheQueries = false; ?*4zNhL
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privateString queryCacheRegion; zjmc>++<t
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publicvoid setCacheQueries(boolean jo^*R'}
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cacheQueries){ fVM%.`
this.cacheQueries = cacheQueries;
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} XHr{\/4V
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publicvoid setQueryCacheRegion(String *u}):8=&R
}W<L;yD
queryCacheRegion){ mI# BQE`p6
this.queryCacheRegion = EB#z\
iJi|* P5dw
queryCacheRegion; _MU'he^W
} P*SXfb"HC
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publicvoid save(finalObject entity){ zP9!fA
getHibernateTemplate().save(entity); X$*
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} m"*:XfOL
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publicvoid persist(finalObject entity){ oZ}e
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getHibernateTemplate().save(entity); g:Dg?_o
} D&shrKFx
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publicvoid update(finalObject entity){ 61'7b`:(hi
getHibernateTemplate().update(entity); ?,j:Y0l.L
} !4E:IM63
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publicvoid delete(finalObject entity){ ^tv*I~>J!
getHibernateTemplate().delete(entity); {x8`gP\H
} XP7A.I#q0
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publicObject load(finalClass entity, ? _W*7<
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finalSerializable id){ 181P;R=}<
return getHibernateTemplate().load i"'k|TGW^
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(entity, id); CqoL5qt
} PT;$@q8
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publicObject get(finalClass entity, &l Q j?]
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finalSerializable id){ `G'V9Xs(
return getHibernateTemplate().get vZ08/!n
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(entity, id); gvC2\k{
} -4Xr5j%o
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publicList findAll(finalClass entity){ c|7Pnx%gT
return getHibernateTemplate().find("from R8 m/Nt2
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" + entity.getName()); qb_V
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} d>%_<pw
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publicList findByNamedQuery(finalString )L{\k$r!EM
rdb%/@.-
namedQuery){ |3i~?]
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return getHibernateTemplate NB^.$39n
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().findByNamedQuery(namedQuery); sJr$[?
} C>+UZ
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publicList findByNamedQuery(finalString query, F JzjS;
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finalObject parameter){ t3M/ThIE
return getHibernateTemplate ,Xn%-OT
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().findByNamedQuery(query, parameter); IQM!dC
} #U1soZ7
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publicList findByNamedQuery(finalString query, HV sIbQS
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finalObject[] parameters){ 6?_Uow}
return getHibernateTemplate 0`x<sjG\q
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().findByNamedQuery(query, parameters); b ,cvQD
} L$b9|j7
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publicList find(finalString query){ .,c8cq?
return getHibernateTemplate().find ;7hf'k
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(query); PQfx0n,
} C{c (K!
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publicList find(finalString query, finalObject u4S3NLG)
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parameter){ D1w_Vpz
return getHibernateTemplate().find :>,d$f^tqE
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(query, parameter); H1l'\
} os2yiF",
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public PaginationSupport findPageByCriteria X)yTx8v4
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(final DetachedCriteria detachedCriteria){ nhIITfJJ
return findPageByCriteria J@Li*Ypo
vH?/YhH|
(detachedCriteria, PaginationSupport.PAGESIZE, 0); RH`m=?~J,
} KAe)
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public PaginationSupport findPageByCriteria }n<dyX:a
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(final DetachedCriteria detachedCriteria, finalint |6&"r&
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startIndex){ <q!{<(:
return findPageByCriteria Jjy}m0)#W_
^=t yf&"
(detachedCriteria, PaginationSupport.PAGESIZE, 6s Pd")%G
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startIndex); [iDa6mcth
} iBZ+gsSP
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public PaginationSupport findPageByCriteria kh`X92~
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(final DetachedCriteria detachedCriteria, finalint ]-R8W/fDn
J)R2O4OEd
pageSize, LJBoS]~
finalint startIndex){ 0S' EnmG
return(PaginationSupport) t >8t|t+
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getHibernateTemplate().execute(new HibernateCallback(){ D.HAp+lx
publicObject doInHibernate =^{^KHzIl3
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(Session session)throws HibernateException { ^lQej%
Criteria criteria = t$}+oCnkv
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detachedCriteria.getExecutableCriteria(session); 0[PP-]JS
int totalCount = 9_HEImk
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((Integer) criteria.setProjection(Projections.rowCount =B;)h
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()).uniqueResult()).intValue(); ^m5{:\
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criteria.setProjection 1 ft.ZJ
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(null); iG<|3I
List items = ln3.TR*
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criteria.setFirstResult(startIndex).setMaxResults ?"L>jr(
r*WdD/r|
(pageSize).list(); B[k"xs
PaginationSupport ps = D$j`+`
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new PaginationSupport(items, totalCount, pageSize, %D&FnTa
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startIndex); l]%|w]i\
return ps; //WgK{Mt
} | o+vpy
}, true); mhcJ0\@_
} eqLETo@} *
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public List findAllByCriteria(final +[cm
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DetachedCriteria detachedCriteria){ SBYRN##n_
return(List) getHibernateTemplate /R^!~J50
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().execute(new HibernateCallback(){ -,Q<*)q{
publicObject doInHibernate YpuA,r;"
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(Session session)throws HibernateException { Muarryh}
Criteria criteria = $i =-A
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detachedCriteria.getExecutableCriteria(session); !'+t)h9^
return criteria.list(); )`g[k"yB3
} &*0!${B
}, true); of(Nq@
} [TNYPA>{
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public int getCountByCriteria(final `5>IvrzXrK
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DetachedCriteria detachedCriteria){ "+|>nA=7
Integer count = (Integer) E6n;_{Se/S
<@Ew-JU
getHibernateTemplate().execute(new HibernateCallback(){ NMOTWA}2
publicObject doInHibernate xNjA>S\]W5
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(Session session)throws HibernateException { k5<lkC2z
Criteria criteria = 8o~\L=
l
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detachedCriteria.getExecutableCriteria(session); 8l?]UFM>C
return b#$:XS
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criteria.setProjection(Projections.rowCount 'o5[:=K
uD. 0?*_
()).uniqueResult(); IMVoNKW-
} ^\x
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}, true); C8(sH @
return count.intValue(); V @8X.R>
} lMP|$C
} \f._I+gJ
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用户在web层构造查询条件detachedCriteria,和可选的 VM-J^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 W>+<r9Rt4
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PaginationSupport的实例ps。 9N9|h y
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ps.getItems()得到已分页好的结果集 ib&
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ps.getIndexes()得到分页索引的数组 Q>||HtF$A
ps.getTotalCount()得到总结果数 4N*^%
ps.getStartIndex()当前分页索引 D:){T>
ps.getNextIndex()下一页索引 HLk/C[`u,
ps.getPreviousIndex()上一页索引 O 89BN6p
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 J,jl(=G
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 0E+ +
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一下代码重构了。 LZ^sc
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我把原本我的做法也提供出来供大家讨论吧: .k[Ptx>
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首先,为了实现分页查询,我封装了一个Page类: |Z!C`G[
java代码:
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/*Created on 2005-4-14*/ qf
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package org.flyware.util.page; {'{ssCL
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/** >2N`l
* @author Joa ujDAs%6MZ
* l1YyZ ^Z
*/ BhNwC[G?m
publicclass Page { |n]^gTJt
oq;}q
/** imply if the page has previous page */ tXfB.[U
privateboolean hasPrePage; {K:/(\
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/** imply if the page has next page */ hXYVi6(k
privateboolean hasNextPage; <;W4Th<4
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/** the number of every page */ vW~_+:),e
privateint everyPage; &
yw-y4 =
=axi0q?}
/** the total page number */ S0kH/A
privateint totalPage; [_b10Z'{
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/** the number of current page */ E6BW&Xp
privateint currentPage; vUj7rDT|
Ik~5j(^E-
/** the begin index of the records by the current J2yq|n?2gq
Cvi-4
query */ @-Gf+*GZys
privateint beginIndex; a#KxjVM
nj)M$'
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/** The default constructor */ GAPZt4Z2
public Page(){ mo<g'|0
hZ$* sf
} l*pCG`@J#
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/** construct the page by everyPage oSE'-8(
* @param everyPage #16)7
* */ vE{QN<6T
public Page(int everyPage){
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this.everyPage = everyPage; YIjBKh
}
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/** The whole constructor */ E&]S No<
public Page(boolean hasPrePage, boolean hasNextPage, :90DS_4
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int everyPage, int totalPage, XIf,#9
int currentPage, int beginIndex){ $D8KEkW
this.hasPrePage = hasPrePage; R%SsHu">
this.hasNextPage = hasNextPage; QZ
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this.everyPage = everyPage; SyTcp?H
this.totalPage = totalPage; r+\it&cW+
this.currentPage = currentPage; g5/8u2d
this.beginIndex = beginIndex; R],,-
} C\EZ8
\:^$ZBQr<n
/** #O=^%C7p
* @return FL0[V,
* Returns the beginIndex. *}3~8fu{
*/ us$~6
publicint getBeginIndex(){ )FE'#\
return beginIndex; <@e6zQG
} 0^tF_."Y
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/** vPpbm
* @param beginIndex IRXpk6|
* The beginIndex to set. (z+[4l7
*/ oM QH-\(}
publicvoid setBeginIndex(int beginIndex){ Y`\zLX"_m
this.beginIndex = beginIndex; IjD:
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} [ *R8XXuL
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/** CuU"s)
* @return ^#XxqVdPk
* Returns the currentPage. ;I]TM#qGF
*/ Hm1C|Qb
publicint getCurrentPage(){ d$b{KyUA
return currentPage; Yb414 K
} h4!$,%"''
;%Jp@'46
/** QMHeU>
* @param currentPage m,qU})
* The currentPage to set. C6Dq7~{B
*/ c[J#Hc8;
publicvoid setCurrentPage(int currentPage){ B8;_h#^q
this.currentPage = currentPage; 1rTA0+h
} />)>~_-3
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/** N f1) 5
* @return A~O
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* Returns the everyPage. 5|Vb)QBv%
*/ o%Pi;8
publicint getEveryPage(){ >8 VfijK
return everyPage; w{#%&e(q"
} Iu%/~FgPj{
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/** ?Q:se
* @param everyPage /vSFQ}W
* The everyPage to set. ]qhVxeUm
*/ *)g*5kKN
publicvoid setEveryPage(int everyPage){ ]!0 BMZmf
this.everyPage = everyPage; v;jrAND
} u&r@@p.
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/** ;k(|ynXv
* @return ~d){7OG
* Returns the hasNextPage. )Q~Q.
*/ 5N`g
publicboolean getHasNextPage(){ DpI_`TF#$Z
return hasNextPage; ?jz{fU
} |oPqX %?
7q$9\RR5
/** Ay"x<JB{U2
* @param hasNextPage Q]a5]:0
* The hasNextPage to set. z[IG+2
*/ bbA+ZLZJn
publicvoid setHasNextPage(boolean hasNextPage){ _ 4Hf?m7z
this.hasNextPage = hasNextPage; ~F
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} N~Ax78TX
4$SW~BpQ
/** ]:m*7p\uk
* @return efZdtrKgy
* Returns the hasPrePage. JI@~FD&
*/ tj{rSg7{
publicboolean getHasPrePage(){ sfa T`q
return hasPrePage; ~O|j*T
} tJ2l_M^
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/** {l\v J#r:
* @param hasPrePage kd!f/'E!
* The hasPrePage to set. i|.!*/qF
*/ ^
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publicvoid setHasPrePage(boolean hasPrePage){ e>sr)M
this.hasPrePage = hasPrePage; izmL8U
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} + +D(P=4hi
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/** QBai;p{
* @return Returns the totalPage. .:l78>f
* .Uha %~%
*/ aH,0+ |
publicint getTotalPage(){ [C
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return totalPage; =xai 7iM
} U>ob)-tl
zSDiJ$Xk
/** >d#B149
* @param totalPage ;(VJZ_
* The totalPage to set. M/Bn^A8@
*/ LOR$d^l
publicvoid setTotalPage(int totalPage){ ^Q2K0'm5
this.totalPage = totalPage; ?HZ+fS,-
} :%!=Ej.J
)k0bP1oGS
} >:KPvq!0
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} [D[ZLv
NVJvCs)3f
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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 ^9qncvV
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个PageUtil,负责对Page对象进行构造: B@.U\.
java代码: [rE,fR
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/*Created on 2005-4-14*/ c>=[|F{{e
package org.flyware.util.page; 4)Z78H%>
%w'@:~0
import org.apache.commons.logging.Log; ?%*Zgk!l7
import org.apache.commons.logging.LogFactory; +!.=M8[
"4n_MV>p
/** kw}J~f2
* @author Joa 8%vk"h:u:
* JF24~Q4P
*/ J|,| *t
publicclass PageUtil { yBs
5FH#)
privatestaticfinal Log logger = LogFactory.getLog Q9FY.KUM
{Qlvj.Xw
(PageUtil.class); \>:(++g
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/** ]5uCs[
* Use the origin page to create a new page [$-y8`~(
* @param page oNl_r: G
* @param totalRecords t4F 1[P
* @return :N%]<Mq
*/ 3 T&m
publicstatic Page createPage(Page page, int 0o(/%31]
QJ>+!p*
totalRecords){ oy/#,R_n%
return createPage(page.getEveryPage(), z4_>6sf{
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page.getCurrentPage(), totalRecords); cp[4$lu
} H[!by)H
m:X;dcq'3
/** d&.)Dw
* the basic page utils not including exception Rz*%(2Vz
MLId3#Q
handler 0u)]1
* @param everyPage $p}7CP
* @param currentPage PlTY^N6Hn
* @param totalRecords OW1[Y-o[
* @return page el- %#0
*/ XZIj' a0d
publicstatic Page createPage(int everyPage, int y*|"!FK
70*Y4'u}A
currentPage, int totalRecords){ (MwB%g
everyPage = getEveryPage(everyPage); OG!^:OY
currentPage = getCurrentPage(currentPage); mhT3 Fwc
int beginIndex = getBeginIndex(everyPage, b[$l{RQ[?
bBC3% H^
currentPage); 3ef]3
int totalPage = getTotalPage(everyPage, 8;Yx a8i e
cKF 8(
totalRecords); 4}fG{Bk
boolean hasNextPage = hasNextPage(currentPage, o D:?fs]
\BUr2]
totalPage); L[Tr"BW
boolean hasPrePage = hasPrePage(currentPage); ?w /tq!
R9fM9
returnnew Page(hasPrePage, hasNextPage, /R 2:Js
everyPage, totalPage, u@[D*c1!H
currentPage, vKol@7%N
a&wl-
beginIndex); BEifUgCh
} z/6eP`jj
#RZW)Br
privatestaticint getEveryPage(int everyPage){ V\X.AGc
return everyPage == 0 ? 10 : everyPage; vYrqZie<
} mqw&SxU9
h-Ffs
privatestaticint getCurrentPage(int currentPage){ VmV/~- <Z
return currentPage == 0 ? 1 : currentPage; !W .ooy5(
} D{ @x
F.^1|+96
privatestaticint getBeginIndex(int everyPage, int >$?$&+e}
Z?CmD;W
currentPage){ w*\)]bTs
return(currentPage - 1) * everyPage; >%'|@75K
} /nGsl<
hJ+>Xm@@!
privatestaticint getTotalPage(int everyPage, int yH@W6' .
I>b!4?h
totalRecords){ ON]
z-
int totalPage = 0; #R'm|En'
N1+%[Uh9)
if(totalRecords % everyPage == 0) Th'6z#h:U
totalPage = totalRecords / everyPage; gtVI>D'(W
else g' H!%<
totalPage = totalRecords / everyPage + 1 ; 8L6!CP_!
%R-"5?eTtu
return totalPage; W32bBzhL
} 1[:?oEI
$iupzVrro
privatestaticboolean hasPrePage(int currentPage){ Jc(tV(z
return currentPage == 1 ? false : true; yG2j!D
} Nt'(JAZ;
G8Ns?
privatestaticboolean hasNextPage(int currentPage, y]+i.8[
u])N^AY"sj
int totalPage){ 50uNgLs
return currentPage == totalPage || totalPage == /i"L@t)\t
YeptYW@xfw
0 ? false : true; _;L9&>!p6
} i|)<#Ywl
9ZeTS~i
~X*)gS-=
} mp+
%@n.;
4}gqtw:
W;eHDQ|
W`C2zbC
^ejU=0+cN
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 %Z}A+Rv+*m
E5/-?(N
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ~OAS T
I+kDx=T!
做法如下: -c~nmPEG6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 BD\xUjd?)Q
TmvI+AY/
的信息,和一个结果集List:
sas;<yh
java代码: -
b:&ACY
#Bj.#5
~?H _?}e
/*Created on 2005-6-13*/ ~(~fuDT~O
package com.adt.bo; =*~]lz__M
@M?;~M?B]J
import java.util.List; 27<~m=`}d
Ma2sQW\
import org.flyware.util.page.Page; p.SEW5
&S>m+m'
/** nX7{09
* @author Joa H3H3UIIT_
*/ ?;ZTJ
publicclass Result { FrIgu k1
2$V]XSe
private Page page; ^dJ/>?1
K|[[A)tt6
private List content; "\Zsr6y
UpF,e>s
/** XkDjA#nx`
* The default constructor PxhB=i!'$
*/ kXFgvIpg<
public Result(){ RLu y;z
super(); [nZ3}o
} pd?3_yU
BA4qQCS;5
/** ps\A\aggML
* The constructor using fields _?x*F?5=
* b%IRIi&,
* @param page m-xSF]q=<
* @param content PO%Z.ol9
*/ LBh|4S$K
public Result(Page page, List content){ rwWs\~.H
this.page = page; :aS8%m
this.content = content; F4xYfbwY"]
} R^.E";/h
C!6?.\U/:c
/** 9%^q?S/Rv
* @return Returns the content. 66NJ&ac
*/ U p=J&^.
publicList getContent(){ O8%+5l`T!
return content; =;#+8w=^
} 0>}
FNRC
h:\WW;s[B
/** dO
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* @return Returns the page. v9QR,b`n
*/ /GCI`hx>"
public Page getPage(){ %JF.m$-
return page; iG( )"^G
} ~>2@55wElp
!C]0l
/** Cbv$O o*
* @param content }pxMO? h$
* The content to set. e <2?O
*/ `O4Ysk72x9
public void setContent(List content){ 3WZdP[o!
this.content = content; ZV=O oLt,
} E%@,n9T~"
7D PKKvQ
/** ,Dd
)=
* @param page `a2%U/U
* The page to set. SIQ 7oxS4
*/ q$6fb)2I]e
publicvoid setPage(Page page){ "Qj;pqR
this.page = page; 1AiqB Rs
} 8@pY:AY
} 3 (Bd`=9
=|_:H$94
-T3 z@k
E_ #MQ;n
yE1M+x./
2. 编写业务逻辑接口,并实现它(UserManager, AJ1(q:P
0~
!).f
UserManagerImpl) d~n|F|`:
java代码: ZZ|a`U
53=5xE= `D
nQm7At
/*Created on 2005-7-15*/ KKB&)R
package com.adt.service; *S ,5
{/d<Jm:
import net.sf.hibernate.HibernateException; fl%X>\i/7
vcm66J.14
import org.flyware.util.page.Page; 8s^CE[TA
Awy-kou[C
import com.adt.bo.Result; qYjR
GF]V$5.ps
/** G>"=Af(t?Y
* @author Joa ?XOl>IO
*/ 0*G
=~:
publicinterface UserManager { 6?GR+;/
UolsF-U}'
public Result listUser(Page page)throws bWU4lPfP
r: Ij\YQ
HibernateException; 2GB)K?1M
/BeA-\B
} 2UqLV^ZY
EMK>7 aks
B.
'&[A
"*E06=fiG
YhQ;>Ko
java代码: =SMI,p&
-CePtq`
.&Tcds
/*Created on 2005-7-15*/ ++{,1wY\
package com.adt.service.impl; g>].m8DZ'
/*Xr^X6
import java.util.List; Ed6k7
e\o>(is
import net.sf.hibernate.HibernateException; }_,1i3Rip
W%$sA}O
import org.flyware.util.page.Page; %#7NCdk;S
import org.flyware.util.page.PageUtil; i
b$2qy
|KH9 81
import com.adt.bo.Result; }C6RgE.6<
import com.adt.dao.UserDAO; ]nmVT~lBe"
import com.adt.exception.ObjectNotFoundException; H$G`e'`OZ
import com.adt.service.UserManager; N`o[iHUj \
V+04X"
/** {DfXn1Cg0U
* @author Joa FZdZGK
*/ CG!7BP\
publicclass UserManagerImpl implements UserManager { '8RBR%)y
d#l z^Ls2
private UserDAO userDAO; Ky:y1\K1^K
mQ~0cwo)
/** v>S[}du
* @param userDAO The userDAO to set. 6d%V=1^F
*/ [22>)1<(
publicvoid setUserDAO(UserDAO userDAO){ O4Z_v%2M
this.userDAO = userDAO; FR5P;Yz%H
} QY)hMo=|o8
PRTn~!Z0
/* (non-Javadoc) ePD~SO9*
* @see com.adt.service.UserManager#listUser '+8`3['
4n}tDHvd
(org.flyware.util.page.Page) g$CWGB*%lm
*/ R H^!7W*
public Result listUser(Page page)throws u(kacQ7
',>Pz+XKc
HibernateException, ObjectNotFoundException { jPu m2U_
int totalRecords = userDAO.getUserCount(); YoU|)6Of
if(totalRecords == 0) ],.1=iY
throw new ObjectNotFoundException DAvF ND$=
()cqax4
("userNotExist"); ON()2@Y4
page = PageUtil.createPage(page, totalRecords); gjbSB6[
List users = userDAO.getUserByPage(page); vZ0K1UTEXY
returnnew Result(page, users); e"I+5r",
} m@A?'gD
3]z%C'
} u[Ij4h.
%]U'
8Pgw_ 21N1
PjxZ3O
s28t'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 &-e@Et`Pg
B_ x?s
询,接下来编写UserDAO的代码: V DN@=/
3. UserDAO 和 UserDAOImpl: Gt|m;o
java代码: _/\U
cT&!_g#g
:_0"t-
/*Created on 2005-7-15*/ 'c6t,%
package com.adt.dao; IH2V.>h
3=@lJ?Ym
import java.util.List; A
,$CYLj+
O/{X:Ja{
import org.flyware.util.page.Page; ,JU3w
tjId?}\
import net.sf.hibernate.HibernateException; QGq8r>
O~udlVn<6
/** LtK= nK
* @author Joa m ?)k&{I
*/ @,\J\ rb
publicinterface UserDAO extends BaseDAO { ?D?ldg
(H[.\O-`
publicList getUserByName(String name)throws K5"8zF)*
p)k5Uh"
HibernateException; v9_7OMl/x
o1k
X` Eu
publicint getUserCount()throws HibernateException; #s}&
q4xP<b^
publicList getUserByPage(Page page)throws l.iT+T
Md5|j0#p
HibernateException; n)bbEXO
pPD}>q
} .@`5>_
<Na .6P
z&Kh$ $)[
C"
2K U*
g^mnYg5
java代码: SJai<>k h
~!iZn
FpYeuH%
/*Created on 2005-7-15*/ JjC&
io
package com.adt.dao.impl; iTu~Y<'m
c|2+J:}p
import java.util.List; CTP!{<ii
tbm/gOBw
import org.flyware.util.page.Page; YLU.]UC
. l>.
import net.sf.hibernate.HibernateException; :|z.F+-/
import net.sf.hibernate.Query; =cwdl7N&I
~:xR0dqx
import com.adt.dao.UserDAO; `=.A])>
CU+H`-+"J
/** 86f8b{_e"
* @author Joa <t"KNKI
*/ .Y*jL &!
public class UserDAOImpl extends BaseDAOHibernateImpl eelkK,4
c`agrS:P
implements UserDAO { b+tm[@|,v
TOge!Q>a
/* (non-Javadoc) p?H2W-
* @see com.adt.dao.UserDAO#getUserByName nYE''g+x
F5s`AjU
(java.lang.String) QP~Iz*J'
*/ E
5N9.th
publicList getUserByName(String name)throws =#.qe=
xO0}A1t
Wd
HibernateException { LUfo@R
String querySentence = "FROM user in class 6-t:eo9
GS@Zc2JPF
com.adt.po.User WHERE user.name=:name"; 6=3;(2u[C"
Query query = getSession().createQuery DPM4v7 S
iQ8T3cC+
(querySentence); sz@Y$<o
query.setParameter("name", name); c*DBa]u2
return query.list(); u$Ty|NBjn
}
oHR@*2b
#DkdFy
%`
/* (non-Javadoc)
s*9lYk0
* @see com.adt.dao.UserDAO#getUserCount() T/nG\WZbZn
*/ >MLPmER
publicint getUserCount()throws HibernateException { D6vhW:t8?
int count = 0; w^=uq3X?
String querySentence = "SELECT count(*) FROM M=t;t0
l\"wdS}
user in class com.adt.po.User"; ,1e\}^
Query query = getSession().createQuery -& T.rsp
bqcwZ6r<
(querySentence); 9?Q0O\&uP
count = ((Integer)query.iterate().next E(miQ
#8CeTR23cw
()).intValue(); d]I3zSIC
return count; i~i
?M)
} >mUSRf4
n?S~(4%
/* (non-Javadoc) &j!q9F
* @see com.adt.dao.UserDAO#getUserByPage Gg# 1k TK
J_}Rsp ED
(org.flyware.util.page.Page) iVZX
*/ m_C#fR /I
publicList getUserByPage(Page page)throws \L:+k `
Sh;Z\nj
HibernateException { ^EZ?wdL
String querySentence = "FROM user in class $l/w.z
X 3(CY`HH[
com.adt.po.User"; )=Ens=>Z
Query query = getSession().createQuery C)(/NGf
!9]q+XefJ
(querySentence); c-`izn]
query.setFirstResult(page.getBeginIndex()) |TQa=
.setMaxResults(page.getEveryPage()); Rwe!xY^d8
return query.list(); w@i;<LY.
} W;^6=(&xn
#%{x*y:Ms
} .gs:.X)TG9
R&@NFin
8!|LJI
LLU]KZhtY|
z *~rd2
至此,一个完整的分页程序完成。前台的只需要调用 +OeoA{-W
<Url&Z
userManager.listUser(page)即可得到一个Page对象和结果集对象 7$A=|/'nSA
-/LB-t
的综合体,而传入的参数page对象则可以由前台传入,如果用 yo]8QO]97
(P|k$S?m
webwork,甚至可以直接在配置文件中指定。 FKU)# Eo
&.chqP(|
下面给出一个webwork调用示例: 39oI
&D>8
java代码: `(&GLv[i^2
5D<"kT
=(Pk7{
/*Created on 2005-6-17*/ IcUE=J
package com.adt.action.user; ,ek0)z.
JXqwy^f
import java.util.List;
XM<
-}KW"#9c
import org.apache.commons.logging.Log; 'da$i
import org.apache.commons.logging.LogFactory; Ch7&9NW
import org.flyware.util.page.Page; ds:&{~7L<T
.s`7n
*xz
import com.adt.bo.Result; 5O]eD84B
import com.adt.service.UserService; 9RmdQ]1n4
import com.opensymphony.xwork.Action; K/|qn)
hO..j
/** GK[[e~#u
* @author Joa nna boD
*/ [WN2ZQ
publicclass ListUser implementsAction{ ,'a[1RN
a{+;&j[!
privatestaticfinal Log logger = LogFactory.getLog NUM+tg>KM
;s!GpO7 +
(ListUser.class); ,%$Cfu
fk'DJf[M
private UserService userService; Q|tzA10E
6UAw9
'X8
private Page page; jM;?);Dd
CQI\/oaO
privateList users; o0#zk
IIUTo
/* 7~2V5@{<
* (non-Javadoc) 2O
"
~k
*
dEK bB
* @see com.opensymphony.xwork.Action#execute() gjc[\"0a5h
*/ G4QsR7
publicString execute()throwsException{ 'tMS5d)4:
Result result = userService.listUser(page); 1)!?,O\ey
page = result.getPage(); n$E'+kox
users = result.getContent(); 17S<6j#H5
return SUCCESS; ?X3uPj9if
} #(1R:z\:
`(VVb@:o
/**
S)W(@R+@4
* @return Returns the page. wOr pp3I
*/ Gn>~CoFN
public Page getPage(){ '$Fu3%ft
return page; :Nl.< 6+
} ,N@N4<C]
BBHoD:l
/** sp&g
* @return Returns the users. jOU1F1
*/ 3 ,
nr*R!
publicList getUsers(){ ]X<L~s_*
return users; v\Edf;(
} =`MMB|{6
?Y'r=Q{w
/** Na{&aqdz
* @param page K?H(jP2mpM
* The page to set. 1SY3
*/ V2BsvR`
publicvoid setPage(Page page){ 2X|nPhNi
this.page = page; RxXiSc`^z
} PLs(+>H
_0!<iN L
/** d1hXzJs
* @param users #b+>O+vx8
* The users to set. &d i=alvv1
*/ g0Jy:`M
publicvoid setUsers(List users){ `!7QegJa"
this.users = users; oxJ#NGD
} ^|lG9z%Foy
6M X4h
/** ~[`*)(4E
* @param userService `fUPq
;
* The userService to set. am#(ms
*/ W;ADc2#)
publicvoid setUserService(UserService userService){ %\?Gzc_
this.userService = userService; [Ontip
} u\P)x~-TM
} t0+D~F(g
^ Mw=!n[
'~OKt`SfIo
T8\%+3e.
#PZBh
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, kYU!6t1
TTm
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 (5&l<u"K~
)`-vN^1S-
么只需要: of>}fJ_p
java代码: H'wh0K(
XYHVw)
*&vi3#ur
<?xml version="1.0"?> nQM7@"R
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork un(fr7NW
gfmaO]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- b@yFqgJ_
4!0nM|~
1.0.dtd"> 9}Qrb@DT
7kH
GU
<xwork> KSy.
UCS`09KNJ
<package name="user" extends="webwork- DY!mq91
[nG[@)G~0M
interceptors"> 4{J'p19
A3mS Sc6
<!-- The default interceptor stack name k80!!S=_>
;P2(C >|
--> [Se0+\,&
<default-interceptor-ref 8!VFb+
6 jo+i[h
name="myDefaultWebStack"/> u(P;) E"1
<nE |Y@S
<action name="listUser" <n|.Z-gF\
Q5pm^X._j
class="com.adt.action.user.ListUser"> jN^09T49
<param ~[9(}UM
:R9 DJh\
name="page.everyPage">10</param> /7-qb^V
<result AlQ
B(U0 ~{7a
name="success">/user/user_list.jsp</result> @AAkEWo)_
</action> 1PdxoRa4=
o;M-M(EZQ6
</package> f+Da W
8et.A
</xwork> }t9A#GOz
9G=ZB^
ky98Bz%
{;j@-=pV
>" z&KZKI
>Gyg`L\
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 {uuvgFC
Il,^/qvIY
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。 5,1q%
@dp1bkU
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 qvhol
RXU#.=xvy
6
&)fZt
."\&;:ZNv
=*?2+ ;
我写的一个用于分页的类,用了泛型了,hoho )XAD#GYM
t(F] -[
java代码: 4*aNdh[t.
@C fxPA
~ E|L4E
package com.intokr.util; yNu%D$6u7
J>Uzd,
/
import java.util.List; *^5..0du
%Jc>joU
/** x#s=eeP1
* 用于分页的类<br> VIjsz42C
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^XQr`CqI
* H<6/i@ly
* @version 0.01 ,0R2k `m!
* @author cheng ooPH [p
*/ $6]7>:8mz
public class Paginator<E> { N}2xt)JZz
privateint count = 0; // 总记录数 Fl^}tC
privateint p = 1; // 页编号 Y8yRQz u
privateint num = 20; // 每页的记录数 !.ot&EbE
privateList<E> results = null; // 结果 KU}HVM{
Kzd`|+?'`M
/** h7H#sL[^
* 结果总数 'of5v6:8
*/ v|v^(P,o
publicint getCount(){ \PB ~6
return count; 044*@a5f
} [ZP8[Zl'?
zu
Jl #3YP
publicvoid setCount(int count){ `+(|$?C u
this.count = count; GL_a`.=@
} ~CB6+t>
iEf6oM
/** Eb<iR)e H=
* 本结果所在的页码,从1开始 = ?hx+-'
* t $+46**
* @return Returns the pageNo. OgTE^W@
*/ Ur]~>-Z
publicint getP(){ ]d@@E_s]
return p; ~4~-^
t
} -\`n{$OR
2S\~
/** =e)[?{H
* if(p<=0) p=1 +jD{O @9
* *YFe
* @param p r4~Bn7j2
*/ i cf[.
publicvoid setP(int p){ C||A[JOS
if(p <= 0) G'<J8;B*
t
p = 1; .bYDj&]P{
this.p = p; &!{wbm@
} ~OXC6z
PIuk]&L^
/** L/w9dk*uv
* 每页记录数量 :fr 2K
*/ %8T:r S
publicint getNum(){ {daNw>TH
return num; h
!~u9
} 6SMGXy*]^
e_wz8]K)n
/** }V3p <
* if(num<1) num=1 Qj? G KO
*/ 4><b3r;T'
publicvoid setNum(int num){ )CzWq}:
if(num < 1) In0kP"
num = 1; *a@pZI0'
this.num = num; K'%,dn
} rSD!u0c[
|Mp_qg?g
/** .6[xX?i^T
* 获得总页数 =>hq0F4[;
*/ WG;1[o&
publicint getPageNum(){ j}chU'if
return(count - 1) / num + 1; ^ZFbp@#U
} ~4wbIE_rN
;C%D+"l1g
/** hgE!)UE
* 获得本页的开始编号,为 (p-1)*num+1 1WPDMLuN
*/ }`$:3mb&f
publicint getStart(){ aho;HM$hjP
return(p - 1) * num + 1; C9/?B:
} p1HU2APFP
j$#pG
/** DsqsMlB{
* @return Returns the results. `
BH8v
*/ k3[
~I'
publicList<E> getResults(){ Ou;
]>FJ
return results; XQ<2(}]4
} `OnN12`
n]x4twZ
public void setResults(List<E> results){ JBa=R^k
this.results = results; YizJT0$
} 9o P8| <+
J?-"]s`J
public String toString(){ %#NaM\=8v
StringBuilder buff = new StringBuilder sb_>D`>
`-4c}T
(); HB\y [:E
buff.append("{"); !cLX1S
buff.append("count:").append(count); A~-e?.
buff.append(",p:").append(p); K$Y!d"D
buff.append(",nump:").append(num); H!&]Di1Eh
buff.append(",results:").append ;tI=xNre`1
FpfOxF6A3
(results); !xMyk>%2
buff.append("}"); I?"cEp
return buff.toString(); _{,e-_hYM
} MyuFZ7Q4$
mY.[AIB
} sRo%=7Z
r,i^-jv;
tCK%vd%