Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 N1l&$#Fr!s
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 |)pgUI2O[
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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 -MTO=#5z
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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 _VFL}<i
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分页支持类: -)o0P\cTEt
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java代码: Q%Y rm
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package com.javaeye.common.util; K4|{[YpPB
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import java.util.List; ]>"q>XgnI
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publicclass PaginationSupport { 0Ik}\lcn
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publicfinalstaticint PAGESIZE = 30; wJb"X=i*
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privateint pageSize = PAGESIZE; P;~P:qKd
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privateList items; d\{a&\v
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privateint totalCount; AOVoOd+6
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privateint[] indexes = newint[0]; 2Hj;o
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privateint startIndex = 0; 1u\kxlZ
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public PaginationSupport(List items, int N \Wd0b
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totalCount){ ypA)G /;
setPageSize(PAGESIZE); (g
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setTotalCount(totalCount); /&Vgo~.J
setItems(items); a"|\n_
setStartIndex(0); u*C"d1v=
} C~([aH@-I
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public PaginationSupport(List items, int sXmo.{Ayb
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totalCount, int startIndex){ /@~&zx&_
setPageSize(PAGESIZE); y+D"LeCAad
setTotalCount(totalCount); 3V2w1CERE
setItems(items); j"Vb8}
setStartIndex(startIndex); 9CW8l0
} j9IeqlL
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public PaginationSupport(List items, int 9X[}ik0
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totalCount, int pageSize, int startIndex){ q=|0lZ$`V_
setPageSize(pageSize); R404\XGL
setTotalCount(totalCount); ;th]/ G
setItems(items); !YJ^BI
setStartIndex(startIndex); /qalj\ud
} nM,5KHU4a
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publicList getItems(){ i<%
return items; I-`qo7dQ_S
} W=)wiRQm
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publicvoid setItems(List items){ ^68BxYUoD\
this.items = items; c?1:='MC
} xFcRp2W9R
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publicint getPageSize(){ GOeYw[Vh
return pageSize; U~Ai'1?xz
} $={WtR
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publicvoid setPageSize(int pageSize){ t <Z)D0.
this.pageSize = pageSize; \p&a c&]
} }:5>1FfX=
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publicint getTotalCount(){ F< #!83*%
return totalCount; mp x/~`c
} Q(e 3-a
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publicvoid setTotalCount(int totalCount){ al3[Ph5G
if(totalCount > 0){ nPj/C7j
this.totalCount = totalCount; LpJ_HU7@lk
int count = totalCount / $*u{i4b
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pageSize; }nW) +
if(totalCount % pageSize > 0) P!JRIw
count++; }ST0?_0F*
indexes = newint[count]; yv!,iK9
for(int i = 0; i < count; i++){ +J~q:b.
indexes = pageSize * yfD)|lK
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} A-dL_3
}else{ H#joc0?P
this.totalCount = 0; FSvtiNW<
} I@f">&^
} ,6%{9oW9Z:
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publicint[] getIndexes(){ 4IIXzMOa
return indexes; sO!YM5v8
} ')ErXLP_
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publicvoid setIndexes(int[] indexes){ 7 vS]O$w<4
this.indexes = indexes; ?=]*r>a3
} Q(}TN,N
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publicint getStartIndex(){ <p'~$vK
return startIndex; 9%?'[jJ
} h69: Tj!
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publicvoid setStartIndex(int startIndex){ cJ%u&2J_
if(totalCount <= 0) .+H8c.
this.startIndex = 0; _`JYA
elseif(startIndex >= totalCount) <h/\)bPB
this.startIndex = indexes oK GF Dl]3
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[indexes.length - 1]; "}bk
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elseif(startIndex < 0) $o"PQ!z
this.startIndex = 0; C_[V[k0(
else{ lxRzyx
this.startIndex = indexes FRicHs n
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[startIndex / pageSize]; U=C8gVb{Hq
} "Q~6cH[#
} |f^/((:D
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publicint getNextIndex(){ 3mIX9&/
int nextIndex = getStartIndex() + sg(L`P
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pageSize; -ANp88a
if(nextIndex >= totalCount) c
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return getStartIndex(); W?"Z>tgp
else yD`{9'L
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return nextIndex; >?,arER
} ?wps_XU
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publicint getPreviousIndex(){ U4_<
int previousIndex = getStartIndex() - *HmL8c
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pageSize; tIb?23K0
if(previousIndex < 0) T[=XGAJ
return0; _9Kdcoh
else hnM|=[wM
return previousIndex; O\L(I079
} <ZJ>jZV0*
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} }TRr*]
P<%
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抽象业务类 0>-l {4srs
java代码: l%"eQ
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/** ij6M E6
* Created on 2005-7-12 Y. yM 1 z
*/ jow^~
package com.javaeye.common.business; \PzC:H
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import java.io.Serializable; oJ`ih&Q8
import java.util.List; `"m"qUd
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import org.hibernate.Criteria; >ofS'mp
import org.hibernate.HibernateException; :Qu!0tY
import org.hibernate.Session; U<eVLfSij
import org.hibernate.criterion.DetachedCriteria;
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import org.hibernate.criterion.Projections; qkv.,z"
import pi5Al)0
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org.springframework.orm.hibernate3.HibernateCallback; ?M7nbfy[A@
import 4(&00#Yxg2
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org.springframework.orm.hibernate3.support.HibernateDaoS U;KHF{Vm
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upport; qo.~5
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import com.javaeye.common.util.PaginationSupport; h
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public abstract class AbstractManager extends b0E(tPw5c
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HibernateDaoSupport { @?K(+BGi
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privateboolean cacheQueries = false; v>g1\yIw
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privateString queryCacheRegion; W #qM$
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publicvoid setCacheQueries(boolean &}w,bG$
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cacheQueries){ 8ne'x!1 D
this.cacheQueries = cacheQueries; +F 6KGK[
} 2=!/)hw}
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publicvoid setQueryCacheRegion(String *NDLGdQqz
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queryCacheRegion){ U*k$pp6\b~
this.queryCacheRegion = hS
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queryCacheRegion; VQ<Z`5eV
} NEZF q?
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publicvoid save(finalObject entity){ [ne4lWaE<y
getHibernateTemplate().save(entity); -.g5|B
} d2.eDEOsC
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publicvoid persist(finalObject entity){ ET_}x7
getHibernateTemplate().save(entity); `"(7)T{
} fXIeCn
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publicvoid update(finalObject entity){ $F G4wA
getHibernateTemplate().update(entity); PpU : 4;en
} AGCqJ8`|T
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publicvoid delete(finalObject entity){ m^T$H_*;
getHibernateTemplate().delete(entity); 6Om-[^
} Ko''G5+
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publicObject load(finalClass entity, 9z_Gf]J~
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finalSerializable id){ RLulz|jC
return getHibernateTemplate().load A1%V<im@Z
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(entity, id); N4fuV?E`
} ENJ]
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publicObject get(finalClass entity, P).
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finalSerializable id){ O:lD>A4{
return getHibernateTemplate().get f
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(entity, id); [(ty{
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publicList findAll(finalClass entity){ #wM0p:<
return getHibernateTemplate().find("from S*#y7YKI
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" + entity.getName()); "-<u.$fE
} `r>WVPS|
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publicList findByNamedQuery(finalString mvUYp,JECl
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namedQuery){ 1P2%n[y
return getHibernateTemplate Q
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().findByNamedQuery(namedQuery); #0xvxg%{
} %$]u6GKabi
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publicList findByNamedQuery(finalString query, #llc5i;
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finalObject parameter){ LDPo}ogs
return getHibernateTemplate Nob(bD5SpE
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().findByNamedQuery(query, parameter); 8 (.<
} #C>pA<YJzK
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publicList findByNamedQuery(finalString query, Qr0JJoHT
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finalObject[] parameters){ 'Fc&"(!||
return getHibernateTemplate X% _~9'#%
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().findByNamedQuery(query, parameters); #v(+3Hp
} _|tg#i|Om
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publicList find(finalString query){ `/+7@~[RU
return getHibernateTemplate().find j*xens$)
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(query); ^@[[,1"K
} 2EK\QW o
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publicList find(finalString query, finalObject 8~2A"<{ub
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parameter){ Z6h.gaQ7
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return getHibernateTemplate().find ~}ewna/2
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(query, parameter); bQ
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} lsio\ $
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public PaginationSupport findPageByCriteria F=P|vYL&&
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(final DetachedCriteria detachedCriteria){ *"e[au^8*b
return findPageByCriteria Zs{ `Yf^Q
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); `kj7I{'l%9
} j 6v +S
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public PaginationSupport findPageByCriteria >eUAHmXQ|
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(final DetachedCriteria detachedCriteria, finalint zcZr
)Oh
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startIndex){ 'Ob5l:
return findPageByCriteria R9#Z=f,
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(detachedCriteria, PaginationSupport.PAGESIZE, E&K8hY%5
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startIndex); CWDo_g$
} %5z88-\
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public PaginationSupport findPageByCriteria %pg*oX1VK6
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(final DetachedCriteria detachedCriteria, finalint ~RMOEH.o
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pageSize, \h0e09& I
finalint startIndex){ A6UtpyS*'
return(PaginationSupport) )?TJ{'m
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getHibernateTemplate().execute(new HibernateCallback(){ GzR;`,_O/
publicObject doInHibernate ]\3dJ^q|%
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(Session session)throws HibernateException { zzW^AvR
Criteria criteria = #Ta@A~.L
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detachedCriteria.getExecutableCriteria(session); JTs.NY
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int totalCount = fi,=z
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((Integer) criteria.setProjection(Projections.rowCount L$ ON=$q5
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()).uniqueResult()).intValue(); 6U""TR!
criteria.setProjection qBwqxxTc
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(null); 4l3N#U0Q
List items = twN(]w}Ps|
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criteria.setFirstResult(startIndex).setMaxResults =oHJ_
};KmMpBn
(pageSize).list(); S%T1na^x
PaginationSupport ps = 4a646jg)
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new PaginationSupport(items, totalCount, pageSize, }5S2v+zE
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startIndex); )O+9v}2
return ps; 5GRN1Aov<
} nC*/?y*9
}, true); Ugs<WVp$
} @'U4-x
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ ~O|0.)71]
return(List) getHibernateTemplate gT+/CVj R
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().execute(new HibernateCallback(){ U
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publicObject doInHibernate N4}h_mh^'
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(Session session)throws HibernateException { SBF3\
Criteria criteria = J$P]>By5:
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detachedCriteria.getExecutableCriteria(session); $zbg
return criteria.list(); r8>
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} U$J]^-AS
}, true); |zUDu\MZ{
} i &KbzOY
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public int getCountByCriteria(final v
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DetachedCriteria detachedCriteria){ 6D+k[oHZm
Integer count = (Integer) Gs9jX/#
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getHibernateTemplate().execute(new HibernateCallback(){ Y{S/A *X
publicObject doInHibernate );*GOLka
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(Session session)throws HibernateException { IQ~()/;3d
Criteria criteria = >/n/n{{
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detachedCriteria.getExecutableCriteria(session); vTP_vsdeG
return )a6i8b3
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criteria.setProjection(Projections.rowCount mPh;
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()).uniqueResult(); fU8;CZnx
} m|y]j4
}, true); *X>rvAd3
return count.intValue(); [v&_MQ
} *%8us~w5/
} OkQSqL
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用户在web层构造查询条件detachedCriteria,和可选的 1,mf]7k$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [|>.iH X
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PaginationSupport的实例ps。 mPu5%%
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ps.getItems()得到已分页好的结果集 ,=ICSS~9l
ps.getIndexes()得到分页索引的数组 Vz#cb5:g
ps.getTotalCount()得到总结果数 R'3i { 1
ps.getStartIndex()当前分页索引 Twk zX|
ps.getNextIndex()下一页索引 *oPSkEA{
ps.getPreviousIndex()上一页索引 }I;W
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 QO,y/@Ph
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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 IS!+J.2
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一下代码重构了。 J?]W!V7C
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我把原本我的做法也提供出来供大家讨论吧: t (1z+
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首先,为了实现分页查询,我封装了一个Page类: h%O`,iD2
java代码: olJ9Kfc0
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/*Created on 2005-4-14*/ s)N1@RBR
package org.flyware.util.page; e^FS/=
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/** E*ic9Za8`h
* @author Joa 9-@w(kMu
* tQ/w\6{
*/ mI.*b(Irp
publicclass Page { @-m&X2J+c
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/** imply if the page has previous page */ JE j+>
privateboolean hasPrePage; J+;.t&5R
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/** imply if the page has next page */ k`&mHSk-
privateboolean hasNextPage; (;n|>l?*
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/** the number of every page */ 87HVD Di
privateint everyPage; 15zL,yo
mrJQB I+
/** the total page number */ o1Xk\R{
privateint totalPage; m$o|s1t
hsl8@=_ B
/** the number of current page */ _
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privateint currentPage; W$3p,VTMmB
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/** the begin index of the records by the current 1"'//0
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query */ =DtM.oQ>
privateint beginIndex; xJ3#k;
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/** The default constructor */ Q~]R#S
public Page(){ qV^H vZJ
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} XGUF9arN
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/** construct the page by everyPage :&a|8Wi[W
* @param everyPage RJWlG'i
* */ % va/x]K
public Page(int everyPage){ ['c:n?
this.everyPage = everyPage; e8[*=&
} GJW1|Fk
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/** The whole constructor */ R=IeAuZR4k
public Page(boolean hasPrePage, boolean hasNextPage, w@"|S_E
'rg$%M*(
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int everyPage, int totalPage, <y!BO
int currentPage, int beginIndex){ QQ?` 1W
this.hasPrePage = hasPrePage; 8kqxr&,[
this.hasNextPage = hasNextPage; *</;:?
this.everyPage = everyPage; }&!rIU
this.totalPage = totalPage; 4];NX
this.currentPage = currentPage; h)YqC$A-s
this.beginIndex = beginIndex; q<7Nz]Td
} yx-{}Yj^
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/** YY.;J3C
* @return 2=#O4k.@
* Returns the beginIndex. `R; ct4-
*/ }R>g(q=N
publicint getBeginIndex(){ VRxBi!d
return beginIndex; j$Kubg(I5
} ~gV|_G
p%G\5.GcJL
/** Xu'u"amt
* @param beginIndex PM_q"}-
* The beginIndex to set. ypml22)kz
*/ v&?Bqj
publicvoid setBeginIndex(int beginIndex){ plp).Gq
this.beginIndex = beginIndex; }q~A( u
} Z|j8:Ohz
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)
/** L$jRg
* @return :Z/ig%
* Returns the currentPage. pY:xxnE
*/ bG5c~
publicint getCurrentPage(){ -m__I U
return currentPage; G q:7d]c~T
} )`U T#5
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/** .AV--oA~
* @param currentPage nGP>M#F
* The currentPage to set. XL"e<P;t
*/ }we"IqLb
publicvoid setCurrentPage(int currentPage){ !867DX3*
this.currentPage = currentPage; @@I2bHyvb
} *M8 4Dry`y
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/** 7g=Ze~aq
* @return J"SAA0)@
* Returns the everyPage. }b0qrr
*/ %fxGdzu7.
publicint getEveryPage(){ hup]Jk
return everyPage; PS6G 7
} k|BEAdQ%M
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/** myXp]=Sb?
* @param everyPage Maq{H`
* The everyPage to set. 9t)t-t#P;
*/ @4&sL] (q
publicvoid setEveryPage(int everyPage){ .Oim7JQ8
this.everyPage = everyPage; {UwJg
} s~TYzfA
KR z\ct|
/** i1sc oxX3\
* @return O,DA{> *m
* Returns the hasNextPage. 6bU/IVP
*/ *FqNzly
publicboolean getHasNextPage(){ yJgnw6>r2
return hasNextPage; ^91k@MC
} L6',s4
1*=[%
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/** Q}1PPi,
* @param hasNextPage !IT']kA
* The hasNextPage to set. 2Yyc`o0R;h
*/ ?XeRL<n
publicvoid setHasNextPage(boolean hasNextPage){ NW~n+uk5v
this.hasNextPage = hasNextPage; dLo%+V#/A
} ] e&"CF
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/** 8^HMK$
* @return P+]39p{
* Returns the hasPrePage. #%x4^A9 q
*/ 6 C
publicboolean getHasPrePage(){ !ZB|GLpo6
return hasPrePage; kWr*+3Xq
} 9m8`4%y=
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/** _:TD{ EO$
* @param hasPrePage BI}>"',
* The hasPrePage to set. zf^!Zqn[8z
*/ !iZ*Z Pu
publicvoid setHasPrePage(boolean hasPrePage){ *%g*Np_P
this.hasPrePage = hasPrePage; bluC P|
} m-;u]X=a
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/** =:#$_qR
* @return Returns the totalPage. VCh%v -/
* ww[STg
*/ =`{!" 6a
publicint getTotalPage(){ ~r=u1]z
return totalPage; Kw'A%7^e
} RMsr7M4<91
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/** & {B,m%G
* @param totalPage )0/DY
* The totalPage to set. `<[Zs]Fe4
*/ %M ~X:A;4
publicvoid setTotalPage(int totalPage){ Inr ~9hz
this.totalPage = totalPage; G;,2cu
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} 'e0qdY`
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} A*@!tz<
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Lw-)ijBW
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个PageUtil,负责对Page对象进行构造: b7HS3NYk
java代码: jLcW;7OAC
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/*Created on 2005-4-14*/ _:=w6jCk
package org.flyware.util.page; E7y<iaA{~
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import org.apache.commons.logging.Log; +dR$;!WB3
import org.apache.commons.logging.LogFactory; 8qt|2%
%#"uK:(N
/** Pbz-I3+66
* @author Joa ?^k-)V
* T w/CJg
*/ nuXaZRH
publicclass PageUtil { U4M!RdG
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privatestaticfinal Log logger = LogFactory.getLog &W }ooGg
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(PageUtil.class); G+}|gG8
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/** < R0c=BZ>
* Use the origin page to create a new page pH)V:BmJ
* @param page ,7tN&R_
* @param totalRecords |1;0q<Ka
* @return dZv-lMYBE
*/ 6rdm=8WFA
publicstatic Page createPage(Page page, int }LQ&AIRN
.rax`@\8
totalRecords){ \'j%q\Bl;
return createPage(page.getEveryPage(), 5AQ $xm4
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page.getCurrentPage(), totalRecords); 1<pbO:r
} 0Ac]&N d`
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/** c_&iGQ
* the basic page utils not including exception Ks9"U^bPs
{Pu\KRU
handler o^_z+JFwb
* @param everyPage KJJ8P`Kx
* @param currentPage yQ6{-:`)
* @param totalRecords 9/q4]%`
* @return page ]Jm9D=
*/ =suj3.
publicstatic Page createPage(int everyPage, int 8v c4J5
q'{E $V)E
currentPage, int totalRecords){ tUL(1:-C
everyPage = getEveryPage(everyPage); pSay^9ZI
currentPage = getCurrentPage(currentPage); ^yjc"r%B
int beginIndex = getBeginIndex(everyPage, &!Y^DR/
5qB>Song
currentPage); 4*d_2:|u
int totalPage = getTotalPage(everyPage, hDzKB))<w
sd.:PE <
totalRecords); h dPKeqg7
boolean hasNextPage = hasNextPage(currentPage, L@0DT&5
"5ah{,
totalPage); e-\J!E'1F
boolean hasPrePage = hasPrePage(currentPage); ,,b_x@y*
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returnnew Page(hasPrePage, hasNextPage, $UO7AHk
everyPage, totalPage, - C8h$P
currentPage, (F~eknJ
WWHT;ST
beginIndex); E #8 `X
} vpTS>!i
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privatestaticint getEveryPage(int everyPage){ HI)ks~E/
return everyPage == 0 ? 10 : everyPage; NCl$vc;,
} Ku 56TH!Py
&2#<6=}
privatestaticint getCurrentPage(int currentPage){ Kx$?IxZ
return currentPage == 0 ? 1 : currentPage; (m~MyT#S
} ub./U@1
cM.q^{d`
privatestaticint getBeginIndex(int everyPage, int K|E}Ni
Xy=|qu
currentPage){ rsy'ZVLUj
return(currentPage - 1) * everyPage; 03AYW)"}M
} yz,ak+wp
1&U'pp|T
privatestaticint getTotalPage(int everyPage, int rJKX4,M
DJT)7l {
totalRecords){ Fl^.J<Dz
int totalPage = 0; !Kd/
lDY
*+lnAxRa?
if(totalRecords % everyPage == 0) `L7 cS
totalPage = totalRecords / everyPage; l,-smK69
else enK4`+.7
totalPage = totalRecords / everyPage + 1 ; pA"pt~6
rh/3N8[6
return totalPage; XNd:x{
} %nVnK6[sox
H\8.T:>
privatestaticboolean hasPrePage(int currentPage){ 4- N>#
return currentPage == 1 ? false : true; ^FF{71;
} jZe]zdml
p"JITH:G
privatestaticboolean hasNextPage(int currentPage, hFyN|Dqhds
}DY^a'wJ-
int totalPage){ boJQ3Xc
return currentPage == totalPage || totalPage == qS+'#Sn
NS mo(c>5
0 ? false : true; ~iydp
} N@Bqe{r6j
YtxBkKiJ2V
>0T0K`o
} }0}J
: :e=6i
V]`V3cy1+3
R-bICGSE
^7~=+0cF]
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。 mJ !}!~:
A\.k['!
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 <@(HQuL#
kSoAnJ|
做法如下: N
y7VIh|
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a}El!7RO0
(;V]3CtU*
的信息,和一个结果集List: X7Cou6r
java代码: %[Ia#0'Y@
C} Ewi-
@X
/*Created on 2005-6-13*/ at
]Lz_\
package com.adt.bo; _f{'&YhUU
GDZe6*
import java.util.List; d cYUw]
4,wdIdSm4
import org.flyware.util.page.Page; (gs"2
gP^'4>Jr
/** ,t(y~Z
wJ
* @author Joa rQ@,Y"
*/ |o|0qG@g
publicclass Result { ,r:.
3.
([`-*Hy
private Page page; `"Tx%>E(U
3,S5>~R=
private List content; `{ou4H\
\[+ZKj:
/** Z!^iPB0~D
* The default constructor oIQor%z
*/ WVf;uob{
public Result(){ 33s.p'
super(); 5 S7\m5
} ?N&"WL^|
[{f{E
/** [[LCEw
* The constructor using fields v|CRiwx
* :
R.,<DQM
* @param page y=G
* @param content )u(`s `zd
*/ .lOEQLt
public Result(Page page, List content){ "otP^X.
this.page = page; zA\DI]:+
this.content = content; %(,JBa:G
} Z\4l+.R`
E.}T.St
/** 6*tI~
* @return Returns the content. \62|w HX
*/ "72
_Sw
publicList getContent(){ ^#vWdOlt
return content; C(xdiQJh
} Qm^N}>e
ERCW5b[RT
/** lHT?
* @return Returns the page. li$(oA2
*/ G'#a&6
public Page getPage(){ CQ"5bnR
return page; drNfFx2
} [gqV}Y"Md
oju4.1
/** P0 hC4Sxf
* @param content GyRU/0'BME
* The content to set. ZMy,<wk
*/ 87r#;ND
public void setContent(List content){ AL3zE=BL
this.content = content; {[NBTT9&
} pR; AqDQ
s@K|zOx
/** ko=vK%E[
* @param page
AQ'~EbH(
* The page to set. _LCK|H%v'
*/ BQ2DQ7q
publicvoid setPage(Page page){ -jFvDf,M,D
this.page = page; }9:d(B9;
} G#
.z((Rj
} cQA;Y!Q#
k`'^e/
.ie \3q)
Xj.6A,}^
qMmh2a&
2. 编写业务逻辑接口,并实现它(UserManager, WVir[Kv%
o~*% g.
UserManagerImpl) mj{TqF
java代码: Vj2]-]Cm
EO:i+e]=
j1_CA5V
/*Created on 2005-7-15*/ OU/PB
package com.adt.service; diaLw
:BNqr[=b
import net.sf.hibernate.HibernateException; }BzV<8F
TMT65X!
import org.flyware.util.page.Page; /!P,o}l7
F
MHpa
import com.adt.bo.Result; K.JKE"j)d
Oz-X}eM
/** jLM1~`&
* @author Joa Dc}-wnga
*/ q~T*R<S
publicinterface UserManager { !Hr~B.f7
&?#V*-;^
public Result listUser(Page page)throws HX7"w
69p>?zn
HibernateException; OtBVfA:[
R]/3`X9!d>
} %8DU}}Rj
\h!%U*!7{
T9}G:6
kL*
DU`
<V5(5gx
java代码: L(fOe3
v
@_J~zo
P>9F(#u_(F
/*Created on 2005-7-15*/ MRV4D<NQ
package com.adt.service.impl; L 1H!o!*
pW 2NrBq@w
import java.util.List; b>er 'U
4%Z! *W*
import net.sf.hibernate.HibernateException; xVfAlN37(
-B* = V
import org.flyware.util.page.Page; W_Z%CBjcT
import org.flyware.util.page.PageUtil; +? E~F
onI%Jl sq
import com.adt.bo.Result; iV58 m
import com.adt.dao.UserDAO; ; $i{>mDT
import com.adt.exception.ObjectNotFoundException; zogw1g&C
import com.adt.service.UserManager; hs!a'E
&5h{XSv
/** o:W>7~$jr=
* @author Joa Ej~vp2
*/ c>6dlWTqX
publicclass UserManagerImpl implements UserManager { A,Wwt
[Qw
;6KcX \g-
private UserDAO userDAO; "v@Y[QI
NTbmI$(
/** ]bLI!2Kr
* @param userDAO The userDAO to set. u!hY
bCB
*/
W8z4<o[$
publicvoid setUserDAO(UserDAO userDAO){ O3/][\
this.userDAO = userDAO; A<fKO <d
} ;4>YPH
opU=49b
/* (non-Javadoc) Ti$G2dBO
* @see com.adt.service.UserManager#listUser Z-z^0QO
6<u=hhL
(org.flyware.util.page.Page) r'/&{?Je/
*/ AJ}QS?p8s
public Result listUser(Page page)throws B52n'.
mvgsf(a*'
HibernateException, ObjectNotFoundException { Tsch:r S
int totalRecords = userDAO.getUserCount(); 6Ri+DPf:
if(totalRecords == 0) LM\ H%=*L
throw new ObjectNotFoundException #s>AiD
&&T\PspM
("userNotExist"); 8eq*q
page = PageUtil.createPage(page, totalRecords); l25_J.e
List users = userDAO.getUserByPage(page);
kw{dvE\K
returnnew Result(page, users); 1y'8bt~7Pf
} C~-x637/
kl%%b"h'
} M15Ce)oB1(
>cU#($X$^
Kh&W\\K
'K&^y%~py,
#{K}o}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 0)F.Y,L
Z.'j7(tu
询,接下来编写UserDAO的代码: \kWL:uU
3. UserDAO 和 UserDAOImpl: iMjoatt
java代码: 9^;Cz>6s
PkX4 !
|ecK~+
/*Created on 2005-7-15*/ JYbsta
package com.adt.dao; ,Ei!\U^)
+q n[F70}
import java.util.List; Cm@rXA/
}?G([s56
import org.flyware.util.page.Page; nVB.sab
#O 2g]YH
import net.sf.hibernate.HibernateException; "o_s=^U
y_mTO4\C2
/** X})5XYvA*
* @author Joa ^Gi9&fS,
*/ 3PkVMX
publicinterface UserDAO extends BaseDAO { E$SYXe [,
2_T2?weD5
publicList getUserByName(String name)throws Ig&H0S
WbJ|]}hJ\
HibernateException; Nm$Ba.Rg
abMB-
publicint getUserCount()throws HibernateException; @};
vl
\
SCi\j/a(
publicList getUserByPage(Page page)throws '3<T~t
Z9wKjxu+
HibernateException; Fi+8| /5
^AhV1rBB
} ~:FF"T>
(A(j.[4a
s.|OdC>U =
ly[j=vBV
{%wF*?gk
java代码: =hRo#]{(K
%_Q+@9
[}$jO,H5r
/*Created on 2005-7-15*/ tJBj9{
package com.adt.dao.impl; ^?M# |>
)[b\wrc
import java.util.List; :2t0//@X
='A VI-go5
import org.flyware.util.page.Page; l XpbAW
uB=DC'lkg
import net.sf.hibernate.HibernateException; [>$?/DM
import net.sf.hibernate.Query; 35Ro85j
N\l|3~
import com.adt.dao.UserDAO;
5ENU}0W
h"0)g:\
/** p!>5}f6
* @author Joa knn9s0'Q
*/ }~NM\rm
public class UserDAOImpl extends BaseDAOHibernateImpl gV}c4>v(
%1mIngW=g
implements UserDAO { (H^)wDb
a yYl3
/* (non-Javadoc) jn
+*G<NJ
* @see com.adt.dao.UserDAO#getUserByName t|urvoz
vpq"mpfkh
(java.lang.String) _-|/$ jZ
*/ _u3%16,o
publicList getUserByName(String name)throws Rp+Lu
?;]Xc~
HibernateException { _Z>ny&
String querySentence = "FROM user in class q2b>Z6!5
8vkCmV
com.adt.po.User WHERE user.name=:name"; >,x&L[3
Query query = getSession().createQuery 'yo-`nNFD
BT)PD9CN(
(querySentence); WA6reZ
query.setParameter("name", name); P5KpFL`B
return query.list(); 3xk-D &"
} Spu>
ac
CJjT-(a
/* (non-Javadoc) A^c
(
* @see com.adt.dao.UserDAO#getUserCount() (`&SV$m
*/ .],:pL9d
publicint getUserCount()throws HibernateException { *Sg6VGP
int count = 0; ){LU>MW{&
String querySentence = "SELECT count(*) FROM HvR5-?qQ
QE|x[?7e,!
user in class com.adt.po.User"; (gRTSd T?
Query query = getSession().createQuery mEmgr(W
o2D;EUsNX
(querySentence); ,|g&v/WlC%
count = ((Integer)query.iterate().next )[ QT?;
qeDXG
()).intValue(); 5O(U1
*
return count; Nwj M=GG
} u4tv=+jh
Tn"@u&P
*
/* (non-Javadoc) 7{tU'`P>
* @see com.adt.dao.UserDAO#getUserByPage W|Cs{rBc?
99\lZ{f(
(org.flyware.util.page.Page) +[ng99p
*/ O7]kcA
publicList getUserByPage(Page page)throws @Q7^caG
U3jnH
HibernateException { H|S hi /
String querySentence = "FROM user in class 2:@,~{`#*
OI_Px3)
y
com.adt.po.User"; Co,?<v=Ll
Query query = getSession().createQuery -mP2}BNM
P~#LbUP(
(querySentence); b0sj0w /
query.setFirstResult(page.getBeginIndex()) 7g5Pc_
.setMaxResults(page.getEveryPage()); "/G]M&
return query.list(); l)e6*sDZ,
} 6?ky~CV
Fh/psd
} nA(5p?D+YB
8=@f lK
NFy V02.
NoMlTh(O
v.ow`MO=;
至此,一个完整的分页程序完成。前台的只需要调用 O=vD6@QI
6i;q=N$'
userManager.listUser(page)即可得到一个Page对象和结果集对象 Zt&
7p
LSR0yCU
的综合体,而传入的参数page对象则可以由前台传入,如果用 bXvriQ.UH
EERCb%M8Z
webwork,甚至可以直接在配置文件中指定。 JqUft=p5
iSX HMp4V
下面给出一个webwork调用示例: 1LaJ
hrp?
java代码: B8unF=u
0dIGX |e
.F'Cb)Z
/*Created on 2005-6-17*/ Aj]/A
package com.adt.action.user; +f$
{r7
1,:QrhC
import java.util.List; ,k1ns?i9KH
6-~ZOMlV
import org.apache.commons.logging.Log; G)?j(El
import org.apache.commons.logging.LogFactory; <00nu'Ex1v
import org.flyware.util.page.Page; \x<,Ma=D
QL @SE@"
import com.adt.bo.Result; #)m[R5g(
import com.adt.service.UserService; Em4'b1mDX%
import com.opensymphony.xwork.Action; H?eG5
#]QS
/** Q8A+\LR~)
* @author Joa #F6<N]i
*/ :L6%57
publicclass ListUser implementsAction{ (0l>P]"n
@#*{*
S8
privatestaticfinal Log logger = LogFactory.getLog ?^J%S,
{H>Tv,v|
(ListUser.class); o^/ fr&,9
]yQqx*
private UserService userService; tS Y4'
\vx'+}
private Page page; "!&
o|!2
5R)IL2~
privateList users; 7Le-f
P8#_E{f
/* \[|X^8j
* (non-Javadoc) TD-B\ @_
* P)LQ=b}V#;
* @see com.opensymphony.xwork.Action#execute() wz@[rMf
*/ ,gW$m~\
publicString execute()throwsException{ '"XVe+.O
Result result = userService.listUser(page); FRL;fF
page = result.getPage(); txm6[Io
users = result.getContent(); 'f0R/6h\3s
return SUCCESS; gV$0J?Pr.
} Vx:uqzw#
mE=Tj%+x
/** 2"k|IHs1
* @return Returns the page. 3sRI7g
*/ V
lkJ$f5l
public Page getPage(){ cd~ QGP_C
return page; i!fk'Yt%
} ,$aqF<+;
1NG[
/** cmYzS6f,7
* @return Returns the users. DZ $O%
*/ Q/J <$W*,
publicList getUsers(){ nv(6NV
return users; 9.,IqnP
}
1D2RhM%
!b+!] 2~g}
/** nEP3B'+
* @param page @*uZ+$
* The page to set. .Iz
JJp
*/ |Bv,*7i&
publicvoid setPage(Page page){ ![eY%2;<
this.page = page; iA`.y9'2
} >]A#_p
>I0 a$w
/** ?%lfbZ
* @param users ~0o>B$xJ
* The users to set. &os:h]
C
*/ c>T)Rc
publicvoid setUsers(List users){ K@oyvJ$
this.users = users; bYX.4(R
} ZN&9qw*
jK%Lewq
/** RE-y5.kE^
* @param userService gKmF#Z"\
* The userService to set. _KBa`lhE
*/ d/ @P;YN!
publicvoid setUserService(UserService userService){ ah(k!0PV
this.userService = userService; |+JC'b?,
} )T&r770
} +D[C.is>]}
c+O:n:L
,Ij/
^EC}
fQ-IM/z
Uc
; S@
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, :QHh;TIG=<
rt?*eC1b+Z
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 ux17q>G
Po.by~|
么只需要: ^&c &5S}
java代码: 79k+R9m
+1\t0P24
,% .)mf
<?xml version="1.0"?> G,1g~h%I$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork mtw{7E
/YvwQ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- l%?()]y
nQg_1+
1.0.dtd"> Hq?dqg' %~
1CJAFi>%D
<xwork> dYlVJ_0Zr
q$`>[&I~)
<package name="user" extends="webwork- K!2%8Ej,J
:2XX~|
interceptors"> 6JRFYgI
# $'H?lO
<!-- The default interceptor stack name I=
cayR
`_]Ul I_h
--> I SdB5Va
<default-interceptor-ref TZ}y%iU:mB
S/l6c P
name="myDefaultWebStack"/> fhC| =0XB
Qv]rj]%
<action name="listUser" >LPIvmT4D?
5{v uN)K3
class="com.adt.action.user.ListUser"> yb0Mn*X+
N
<param e nw*[D !
O3#eQs
name="page.everyPage">10</param> e+<9Sh7&
<result FMWM:
Lzcea+*uw
name="success">/user/user_list.jsp</result> l?Ibq} [~
</action> r$x;rL4
1S yG
</package> !!cN4X
#3A|Z=,5
</xwork> C5e;U
(CJx Y(1K
jx
?"`;a
@18}'k
IA`Lp3Z
fX>y^s?y
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 |.-Muv
>&^jKfY
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。 ,/!^ZS*
q0NToVo@
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 QUh`kt(E
^uPg71r:
k~fH:X~x
7 y$a=+D i
oa`7ClzD
我写的一个用于分页的类,用了泛型了,hoho W! J@30
jvo^I$|2h
java代码: Zq5~M bldh
*M$'dLn
!fjB oK+
package com.intokr.util; eo.B0NZsF
a>Zp?*9
import java.util.List; ~=|QPO(d
oArJ%Y>
/** h
9}x6t,
* 用于分页的类<br> C;.,+(G
* 可以用于传递查询的结果也可以用于传送查询的参数<br> TOG:N~
* BO%'/2eV
* @version 0.01 (%"9LYv
* @author cheng _KkP{g,Y
*/ !%.=35NS@E
public class Paginator<E> { z%\&n0
privateint count = 0; // 总记录数 !(Y,2{
privateint p = 1; // 页编号 yT~x7,
privateint num = 20; // 每页的记录数 2 gR*] ?C*
privateList<E> results = null; // 结果 L|6I
qdxaP% p2
/** V)vik
* 结果总数 1I)oT-~
*/ 8 )n g> l
publicint getCount(){ o^m?w0 \
return count; !Lw]aHb
} Rz[3cN)?q
i83[':
publicvoid setCount(int count){ v G9>e&Be
this.count = count; 1l Cr?
} &~2IFp
8_"NF%%(n
/** bZ``*{I/
* 本结果所在的页码,从1开始 C\B4Uu6q
* 4u"Bll
* @return Returns the pageNo. n9n)eI)R
*/ OHrzN']
publicint getP(){ q6<P\CSHy<
return p; a6 1!j>Kx
} }W&9} 9p"
mCG&=Fx
/** c*(^:#"9
* if(p<=0) p=1 ._Ww
* "Mhn?PTq
* @param p j4+Px%sW
*/ L"n)fe$
publicvoid setP(int p){ K[LuvS
if(p <= 0) z?( b|v
p = 1; n.z,-H17
this.p = p; .{} 8mFi1
} C+[)^2M{
i^V(LGQF
/** V; CPn
* 每页记录数量 RS
l*u[fB
*/ Y]](.\ff
publicint getNum(){ ZfK[o{9>
return num; l;L_A@B<
} R&a$w8
0;=-x"
/** >#k-
~|w
* if(num<1) num=1 t(9q6x3|e
*/ RAP-vVh/C
publicvoid setNum(int num){ ;i'[c`
if(num < 1) G\TO]c
num = 1; _B&Lyg!J
this.num = num; Z6A-i@
} $Ery&rX.
7B (%2
/** b*M?\ aA
* 获得总页数 ?Rx(@
*/ -THMTRFz
publicint getPageNum(){ Z0m`%(MJa
return(count - 1) / num + 1; pDSNI2
} XclTyUGoK+
nS*Y+Q^9a
/**
mPk'a
* 获得本页的开始编号,为 (p-1)*num+1 Y`Io}h G$
*/ 1{
%y(?`
publicint getStart(){ ,<r&]
eC
return(p - 1) * num + 1; DQm%=ON7
} }Mt1C~{(
=4a:)g'
/** R]iV;j|
* @return Returns the results. p2{7+m
*/ C?T\5}h
publicList<E> getResults(){ RbXR/Rd
return results; 2_+>a"8Y
} E<[
s+iX
q1( [mHZ
public void setResults(List<E> results){ dkZe.pv$j
this.results = results; Oo}h:3?
} =I@t%Y
0!_?\)X
public String toString(){ zqo0P~
StringBuilder buff = new StringBuilder h<`aL;.g
-HG.GA
(); 0lg$zi x(
buff.append("{"); og5VB
buff.append("count:").append(count); VP~2F
E
buff.append(",p:").append(p); !m+Pd.4TaB
buff.append(",nump:").append(num); 5mD8$%\8
buff.append(",results:").append LV^^Bd8Ct
Pwl*5/l
(results); 6*q1%rs:w
buff.append("}"); Yi*F;V
return buff.toString(); ZH_$Q$9
} 25$_tZPAI
3ic /xy;}
}
usB*Wn8
Fo.Y6/}
P1Hab2%+