Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 u&f|z9
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 AJoP3Zv|?
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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 9'vf2) "
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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 }h sR}
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分页支持类: W:8{}Iu<
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java代码: SEM-t
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package com.javaeye.common.util; {s2eOL5I|%
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import java.util.List; iqWkhJphv
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publicclass PaginationSupport { lI9|"^n7F
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publicfinalstaticint PAGESIZE = 30; ,L\KS^>
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privateint pageSize = PAGESIZE; O4^' H}*
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privateList items; tCj\U+;
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privateint totalCount; nbDjoZZ4
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privateint[] indexes = newint[0]; OskQ[
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privateint startIndex = 0; 5VGZ5,+<<
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public PaginationSupport(List items, int EgOiJH
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totalCount){ }fhGofN$e
setPageSize(PAGESIZE); BMn`t@ !x
setTotalCount(totalCount); , LqfwA|
setItems(items); pA\"Xe&
setStartIndex(0); @~i :8
} +a+DiD>./
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public PaginationSupport(List items, int 8'Q&FW3"
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totalCount, int startIndex){ $A98h-*x
setPageSize(PAGESIZE); k+eeVy
setTotalCount(totalCount);
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setItems(items); B2)5Z]
setStartIndex(startIndex); <II>io;
} fV!~SX6S
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public PaginationSupport(List items, int 4y,pzQ8a
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totalCount, int pageSize, int startIndex){ `mS0]/AV/
setPageSize(pageSize); 7aHP;X~0
setTotalCount(totalCount); )s
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setItems(items); | tFg9RT
setStartIndex(startIndex); ~#=70
} Ece=loV*l
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publicList getItems(){ U@LIw6B!KL
return items; iu`B8yI
} PJ)d5D%T
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publicvoid setItems(List items){ MX|@x~9W
this.items = items; _u#r;h[
} 5^N`~
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publicint getPageSize(){ u)Vn7zh
return pageSize; ?+byRoY>&g
} -[z1r)RZ
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publicvoid setPageSize(int pageSize){ 6 _#C vQ
this.pageSize = pageSize; z'Ut9u
} uA\KbA.c;U
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publicint getTotalCount(){ 4CxU
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return totalCount; DV!0zzJ
} cu4 |!s`#
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publicvoid setTotalCount(int totalCount){ 58PL@H~@0
if(totalCount > 0){ yDi'@Z9R?
this.totalCount = totalCount; +"VXw2R_e
int count = totalCount / rpL]5e!
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pageSize; KN.WTaO
if(totalCount % pageSize > 0) v;Rm42k
count++; A/~^4DR
indexes = newint[count]; oK2j PP
for(int i = 0; i < count; i++){ J+qcA}
indexes = pageSize * Nbt.y 'd
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} #D%l;Ae
}else{ is{H >#+"
this.totalCount = 0; YF)c.Q0
} oox;8d4}y
} ezhK[/E=
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publicint[] getIndexes(){ Qt=OiKZ
return indexes; W'Y#(N[ktP
} GOX2'N\h^
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publicvoid setIndexes(int[] indexes){ !PEP`wEKdp
this.indexes = indexes; e @|uG %
} -D
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publicint getStartIndex(){ N. 0~4H
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return startIndex; \WM"VT
} +VO(6Jn
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publicvoid setStartIndex(int startIndex){ AN+S6t
if(totalCount <= 0) g` 41d
this.startIndex = 0; vk3C&!M<a
elseif(startIndex >= totalCount) Bv^5L>JZ/
this.startIndex = indexes .QDeS|l
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[indexes.length - 1]; Y58et9gRO
elseif(startIndex < 0) f}Uf*Bp
this.startIndex = 0; (q=),3/<pU
else{ P?<G:]W
this.startIndex = indexes E7@m& R
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[startIndex / pageSize]; 1j!{?t?
} ;sY n=r
} 4R9y~~+
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publicint getNextIndex(){ Vd A!tL
int nextIndex = getStartIndex() + CD)JCv
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pageSize; y2>AbrJ
if(nextIndex >= totalCount) \!4_m8?
return getStartIndex(); gLWbd~
else pUeok+k_
return nextIndex; gO_d!x*
} rC6{-42bb
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publicint getPreviousIndex(){ US]I[Y6V
int previousIndex = getStartIndex() - yzyK$WN\[3
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pageSize; b4>1UZGW-
if(previousIndex < 0) Url8&.pw
return0; *^p^tK
else d{(NeT s
return previousIndex; LDj*~\vsq
} BSyS
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} luCwP
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抽象业务类 A{ . A1
java代码: `~2I
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/** u56WB9Z
* Created on 2005-7-12 \y+@mJWa
*/ X`fer%`
package com.javaeye.common.business; 6~a4-5;>z
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import java.io.Serializable; noO#o+
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import java.util.List; )^j62uv
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import org.hibernate.Criteria; 4ms"mIt
import org.hibernate.HibernateException; o}y(T07n
import org.hibernate.Session; {z |+.D
import org.hibernate.criterion.DetachedCriteria; Pk&sY'
import org.hibernate.criterion.Projections; .hK:-q,
import B$_-1^L
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org.springframework.orm.hibernate3.HibernateCallback; 6-f-/$B
import ,7SqRY,+
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org.springframework.orm.hibernate3.support.HibernateDaoS !PJp()
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upport; &|fWtl;43
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import com.javaeye.common.util.PaginationSupport; oe[f2?-
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public abstract class AbstractManager extends aJ
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HibernateDaoSupport { 4,?WNPqo
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privateboolean cacheQueries = false; & DhdB0Hjf
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privateString queryCacheRegion; E*d UJ.>
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publicvoid setCacheQueries(boolean n {..Q,z
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cacheQueries){ %;b] k
this.cacheQueries = cacheQueries;
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} aA'of>'ib|
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publicvoid setQueryCacheRegion(String '8;'V%[+
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queryCacheRegion){ k;jXVa
this.queryCacheRegion = Qn)AS1pL+
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queryCacheRegion; hY|-l%2f
} 05o<fa 2HE
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publicvoid save(finalObject entity){ 'q1cc5(ueV
getHibernateTemplate().save(entity); +nL#c{
} j5rMY=|F
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publicvoid persist(finalObject entity){ O6Y1*XTmH6
getHibernateTemplate().save(entity); TEi1,yc
} ?b\oM
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publicvoid update(finalObject entity){ q I*7ToBJ
getHibernateTemplate().update(entity); hp}JKj@
} =4gPoS
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publicvoid delete(finalObject entity){ Uz%2{HB@{
getHibernateTemplate().delete(entity); _=HNcpDA;0
} $ J!PSF8PL
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publicObject load(finalClass entity, >~ L0M
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finalSerializable id){ g1~wg$`S8S
return getHibernateTemplate().load L+8O
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(entity, id);
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} I?_WV_T&
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publicObject get(finalClass entity, Av!xI
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finalSerializable id){ '~zi~Q7M
return getHibernateTemplate().get q2*1Gn9!j
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(entity, id); vPAL,
} XHh*6Yt_ (
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publicList findAll(finalClass entity){ b"w@am>&
return getHibernateTemplate().find("from YmLpGqNv
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" + entity.getName()); ubMN
} $4hi D;n
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publicList findByNamedQuery(finalString 0/uy'JvWru
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namedQuery){ "G@(Cb*+T
return getHibernateTemplate "iUh.c=0F,
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().findByNamedQuery(namedQuery); A0bR.*3
} S84S/y
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publicList findByNamedQuery(finalString query, +3Z+#nGtk
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finalObject parameter){ z=Xh
return getHibernateTemplate }yw>d\] f
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().findByNamedQuery(query, parameter); *0'< DnGW
} 3 6t^iV*3
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publicList findByNamedQuery(finalString query, `W.g1"o8W4
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finalObject[] parameters){ Gh352
return getHibernateTemplate j{6O:d6([$
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().findByNamedQuery(query, parameters); ~RV"_8`V9
} &a)d,4e<M
+'_ peT.8
publicList find(finalString query){ ,\N4tG1\
return getHibernateTemplate().find MHJRBn{}
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(query); 1C0'
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} )>@%;\qV
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publicList find(finalString query, finalObject 35 L\
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parameter){ LIT`~D
return getHibernateTemplate().find NDJP`FI
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(query, parameter); aLlHR_
} @WiTh'w0
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public PaginationSupport findPageByCriteria 4vV\vXT *
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(final DetachedCriteria detachedCriteria){ fNBI!=
return findPageByCriteria 2w fkXS=~6
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); rPt
} tlB-s;
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public PaginationSupport findPageByCriteria Q{CRy-ha
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(final DetachedCriteria detachedCriteria, finalint @FF80U4'
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startIndex){ `U&'71B^
return findPageByCriteria 1L?d/j
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(detachedCriteria, PaginationSupport.PAGESIZE, [z!pm-Ir
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startIndex); 1DGl[k/zv
} A5Q4wy`
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public PaginationSupport findPageByCriteria {
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(final DetachedCriteria detachedCriteria, finalint oDayfyy4y)
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pageSize, `?SC.KT
finalint startIndex){ DuLl"w\_@
return(PaginationSupport) HMDuP2Y
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getHibernateTemplate().execute(new HibernateCallback(){ uc}F|O
publicObject doInHibernate /:"^,i\t
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(Session session)throws HibernateException { R7O<>kt
Criteria criteria = F>GPi!O
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detachedCriteria.getExecutableCriteria(session); .{|SKhXk
int totalCount = *\cU}qjk
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((Integer) criteria.setProjection(Projections.rowCount Cq'{%
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()).uniqueResult()).intValue(); W8r"dK
criteria.setProjection bZ^'_OOn
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(null); vU(fd!V ?
List items = v*c"SI=@M=
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criteria.setFirstResult(startIndex).setMaxResults hT `&Xb
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(pageSize).list(); ?@kz`BY
PaginationSupport ps = I!SIy&=W
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new PaginationSupport(items, totalCount, pageSize, y]+[o1]-c
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startIndex); 0A-yQzL|
return ps; #lMC#Ld
} ,_s.amL3O{
}, true); u:tcL-;U
} ei"c|/pO
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public List findAllByCriteria(final Q2:rWE{K!
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DetachedCriteria detachedCriteria){ ,~DKU*A_~
return(List) getHibernateTemplate )u4=k(
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().execute(new HibernateCallback(){ U"oHPK3"TA
publicObject doInHibernate )rlkQ'DN
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(Session session)throws HibernateException { H9(UzyN>i
Criteria criteria = W39J)~D^@
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detachedCriteria.getExecutableCriteria(session); a .?AniB0
return criteria.list(); R&g&BF
} h7@%}<%
}, true); `^
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} teC/Uf5
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public int getCountByCriteria(final ` N
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DetachedCriteria detachedCriteria){ +$#XV@@~
Integer count = (Integer) m AET`B "
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getHibernateTemplate().execute(new HibernateCallback(){ L3'isaz&^
publicObject doInHibernate xg 8R>j
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(Session session)throws HibernateException { qnnRS
Criteria criteria = 94|ZY}8|f
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detachedCriteria.getExecutableCriteria(session); BUV4L5(
return %4t?X
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criteria.setProjection(Projections.rowCount QDVSFGwr
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()).uniqueResult(); Bj9FSKiH
} _HjB'XNr(
}, true); SuNc&e#(
return count.intValue(); 33wVP}e5
} MPn/"Fij$
} +$xw0)|
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用户在web层构造查询条件detachedCriteria,和可选的 ld):Am}/o
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Cbl>eKw
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PaginationSupport的实例ps。 g{uiY|
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ps.getItems()得到已分页好的结果集 m-+>h:1b|9
ps.getIndexes()得到分页索引的数组 5w{U/v$Z
ps.getTotalCount()得到总结果数 (FZ8T39
ps.getStartIndex()当前分页索引 ?<Hgq8J
ps.getNextIndex()下一页索引 jC$~m#F
ps.getPreviousIndex()上一页索引 O '`|(L
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Y,EF'Ot
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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 !0|&f>y
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一下代码重构了。 [+#k+*1*o
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我把原本我的做法也提供出来供大家讨论吧: [;4ak)!
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首先,为了实现分页查询,我封装了一个Page类: O8N1gf;t
java代码: ygX!'evY
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/*Created on 2005-4-14*/ $uUyp8F
package org.flyware.util.page; J7e/+W~
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/** ;`kOFg#`)c
* @author Joa S4_ZG>\VT
* +
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*/ |u$*'EsP
publicclass Page { )8n?.keq
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/** imply if the page has previous page */ B|+%ExT7
privateboolean hasPrePage; odJE~\\hw
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/** imply if the page has next page */ gkq~0/
privateboolean hasNextPage; nw_|W)JVQ
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/** the number of every page */ dl |$pm@x
privateint everyPage; h.Sbds
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/** the total page number */ 30(e6T;
privateint totalPage; +W8#] u|
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/** the number of current page */ xdY'i0fh
privateint currentPage; I$)9T^Ra
wdV)M?
/** the begin index of the records by the current m7XN6zX
%u<r_^w5
query */ 'd;aAG
privateint beginIndex; pCa~:q*85
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/** The default constructor */ A)d0Z6G`
public Page(){ E5c)\
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} e%{7CR'~TD
@T.F/Pjhc
/** construct the page by everyPage 8JW0;H<
* @param everyPage J4iu8_eH!D
* */ '-G,7!.,r%
public Page(int everyPage){ \,:7=
this.everyPage = everyPage; wLt0Fq6QG
} 99]s/KD2yb
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/** The whole constructor */ y^kC2DS
public Page(boolean hasPrePage, boolean hasNextPage, a{%EHL,F
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int everyPage, int totalPage, _+}hId
int currentPage, int beginIndex){ YhAO
this.hasPrePage = hasPrePage; /^&$ma\
this.hasNextPage = hasNextPage; /jq"r-S"
this.everyPage = everyPage; irjHPuhcG
this.totalPage = totalPage; akHQ&+[j
this.currentPage = currentPage; |L-- j
this.beginIndex = beginIndex; I>-}ys`[
} *]k E3
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/** ,p\*cHB9
* @return ,pkzNe`F
* Returns the beginIndex. `fVzY"Qv k
*/ cRf;7G
publicint getBeginIndex(){ ~Sd,Tu%:
return beginIndex; HJ!)&xT
} @OHNz!Lj:d
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/** $Df1t
* @param beginIndex +s [_
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* The beginIndex to set. soKR*gJ,
*/ a{?>F&vnU
publicvoid setBeginIndex(int beginIndex){ o+R(ux"
this.beginIndex = beginIndex; I4c%>R
} W>P :EI1
8@T0]vH&
/** G~Y#l@8M+
* @return Xa&:Hg<
* Returns the currentPage. AJzm/,H
*/ lWf(!=0m
publicint getCurrentPage(){ ?:zMrlX
return currentPage;
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} % %2~%FVb
u/\Ipk/
/** otP2qAI
* @param currentPage )S_%Ip
* The currentPage to set. )MX%DQw
*/ x}reeqn
publicvoid setCurrentPage(int currentPage){ Ja@?.gW
this.currentPage = currentPage; C|QJQ@bj0
} :+ "JPF4X
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/** O9{A)b!HB
* @return 8R;E+B{
* Returns the everyPage. BMhuM~?(
*/ rmI@ #'
publicint getEveryPage(){ ;:Kc{B.s
return everyPage; q93V'[)F
} i{J[;rV9
>>=v`}
/** z_z'3d.r7
* @param everyPage q#Ik3 5
* The everyPage to set. Yc(lY
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*/ _ `7[}M~
publicvoid setEveryPage(int everyPage){ Pp|pH|(n ,
this.everyPage = everyPage; fK=vLcH
} wp-3U}P2(
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/** 3v<9 Z9O
* @return rO1.8KKJ
* Returns the hasNextPage. N=:xyv
*/ u)ZZ/|
publicboolean getHasNextPage(){ ['0^gN$:e
return hasNextPage; IRI<no
} c;R.rV<
8EI&}I
/** Z,b^f
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* @param hasNextPage HMR!XF&JjC
* The hasNextPage to set. s|"4!{It
*/ $I/RN
publicvoid setHasNextPage(boolean hasNextPage){ 061 f
this.hasNextPage = hasNextPage; Ob-k`@_|
} )v.\4Q4
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/** 0j{KZy
* @return h3A|nd>\
* Returns the hasPrePage. j;*=
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*/ aK9zw
publicboolean getHasPrePage(){ MK4CggoC
return hasPrePage; ' }NH$ KA
} c-a;nAR
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/** 0 f"M-x
* @param hasPrePage >[g'i+{
* The hasPrePage to set. 7jF2m'(
*/ 2?owXcbx
publicvoid setHasPrePage(boolean hasPrePage){ &44?k:
this.hasPrePage = hasPrePage; ]^l-k@
} Xc]Q_70O
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/** H0mDs7
* @return Returns the totalPage. _n<
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* 9}Zi_xK&|e
*/ E}=F
publicint getTotalPage(){ ~3m}
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return totalPage; &oiBMk`*
} z[_Gg8e
O<w7PS
/** pJwy~ L
* @param totalPage 1uhSP!b
* The totalPage to set. ia/_61%
*/ {{_,YO^w
publicvoid setTotalPage(int totalPage){ 4:v{\R
this.totalPage = totalPage;
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} Jz\'%O'
NW;wy;;
} w2`j&]D6
aw/5#(1R
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&rxR"^x\
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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 3836Di:{
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个PageUtil,负责对Page对象进行构造: LIHf]+
java代码: o>Z+=&BZ@a
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/*Created on 2005-4-14*/ gG=E2+=uy
package org.flyware.util.page; bDPT1A`F
gs77")K&
import org.apache.commons.logging.Log; /-ky'S9
import org.apache.commons.logging.LogFactory; pF"IDC
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/** PK*
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* @author Joa b%,`;hy{
* -f:uNF]Ls
*/ l=JK+uZ
publicclass PageUtil { Zx]"2U#
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privatestaticfinal Log logger = LogFactory.getLog 2]*2b{gF,
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(PageUtil.class); ) 4'@=q
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/** CR$5'#11)
* Use the origin page to create a new page mWM!6"
* @param page 89)rss
* @param totalRecords Y,@{1X`0@3
* @return +P <Lo I
*/ +<H)DPG<
publicstatic Page createPage(Page page, int -.E<~(fad
hw&R.F
totalRecords){ *l^%7Wrk
return createPage(page.getEveryPage(), R#Bdfmldq
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page.getCurrentPage(), totalRecords); 3J}bI{3
} #`4ma:Pj
jM3{A;U2
/** <&rvv4*H
* the basic page utils not including exception YvK8;<k@-?
?79ABm
a
handler Tce2]"^;
* @param everyPage `D%bZ%25c
* @param currentPage lU.@! rGbw
* @param totalRecords U{o0Posg
* @return page Hd)4_
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*/ dLm~]V3
publicstatic Page createPage(int everyPage, int 6l>$N?a
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currentPage, int totalRecords){ x*[\$E`v
everyPage = getEveryPage(everyPage); /wL}+
currentPage = getCurrentPage(currentPage); \6xVIQ& 0
int beginIndex = getBeginIndex(everyPage, v7/qJ9l
e? fFh,a
currentPage); ;,]T|>M
int totalPage = getTotalPage(everyPage, jxr~cp?4
i4N'[ P}
totalRecords); dg4 QA_"
boolean hasNextPage = hasNextPage(currentPage, m>'sM1s
fgP_NYfOj
totalPage); tq^H)
boolean hasPrePage = hasPrePage(currentPage); T?c:z?j_9
m$:o+IH/
returnnew Page(hasPrePage, hasNextPage, gX34'<Z
everyPage, totalPage, *#,wV
currentPage, Jx@3zl
.4~n|d>z
beginIndex); \0m[Ch}~ey
} 70L{u+wIy
j']m*aM1>
privatestaticint getEveryPage(int everyPage){
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return everyPage == 0 ? 10 : everyPage; Cv|ya$}a
} r"a0!]n
gYx|Na,+
privatestaticint getCurrentPage(int currentPage){ (yCFpb
return currentPage == 0 ? 1 : currentPage; #|34(ML
} ;z>)&F
hX]vZR&R
privatestaticint getBeginIndex(int everyPage, int `bffw:;%
=LS?:Mhm
currentPage){ jyf[O -
return(currentPage - 1) * everyPage; @
Sw[+`
} 0*q&)
c?CjJ}-7
privatestaticint getTotalPage(int everyPage, int 9Ay*'
_rK}~y=0
totalRecords){ b&Qj`j4]ZM
int totalPage = 0; jnX9] PkJ
)G0a72
if(totalRecords % everyPage == 0) iU\WV
totalPage = totalRecords / everyPage; <5A(rDij
else B8:_yAv o
totalPage = totalRecords / everyPage + 1 ; &'UYV>
aO?(ZL
return totalPage; e/EfWwqt
} tQB+_q
z
Ym5q#f)|
privatestaticboolean hasPrePage(int currentPage){ {
D1.
return currentPage == 1 ? false : true; T2
0dZ8{y
} ]C-hl}iq
]%3o"|
privatestaticboolean hasNextPage(int currentPage, g6k@E,cI_
YsXP$y]g-
int totalPage){ ?C6iJnm
return currentPage == totalPage || totalPage == o jzO?z
2![.Kbqa%
0 ? false : true; AW4N#gt8',
} 'c\zWmAZ
JB a:))lw
69 R8#M
} :Q=Jn?Gjb
1GVJ3VXt
74rz~ZM
5
e;R5A6|
B i?DmrH
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 vDz)q
Hm4:m$=p4
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 >n)N=Zyu
V4}9f5FR
做法如下: RX%*:lXi_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !MNUp(:
w%)=`'s_
的信息,和一个结果集List: 6|t4\'
java代码: BCk$FM@
iVzv/Lqm1
~oh=QakW
/*Created on 2005-6-13*/ -@-cG\{
package com.adt.bo; .xuLvNyQr
_) 2fXG!
import java.util.List; l=[<gPE
=9GL;z:R+
import org.flyware.util.page.Page; 0Np}O=>
9`+c<j4/B
/** UwrinkoeE
* @author Joa KD*,u{v;
*/ FJgr=9>
publicclass Result { &Jv j@,>$d
wX" 6 S:
private Page page; 5zX;/n~
5V4Ze;K
private List content; z,[4BM
900#K
/** 0~Ot
* The default constructor [s"3g\L';
*/ .{LFc|Z[
public Result(){ yv^j~
super(); `h/j3fmX?
} [S9T@Q
R3<>]/1p|P
/** h #Od tc1)
* The constructor using fields y.26:c(
* =O1N*'e
* @param page ngj=w;7~+
* @param content I4ZL+a
*/ N\1!)b
public Result(Page page, List content){ &/}]9 #
this.page = page; [
/w{,+U
this.content = content;
cHs@1R/-s
} $R%xeih1fz
pHEhB9_A!
/** YA O,
rh
* @return Returns the content. sH(4.36+
*/ r.0IC*Y
publicList getContent(){ Q\ TawRK8
return content; aG}ju;
} : I28Zi*
ao#{N=mn
/** 3:7J@>
* @return Returns the page. -z./6dQ
*/ o {Sc
public Page getPage(){ fDhV
*LqW
return page; U0q{8 "Pl
} LCx{7bN1ro
O&Q_vY
/** N^pTj<M<g
* @param content R<@s]xX_
* The content to set. M5s>;q)
*/ j|TcmZGO
public void setContent(List content){ ;3OQgKI
this.content = content; YwyP+Sr\
} ~UX@%0%)N
(wU<Kpt?J
/** B>*zQb2:
* @param page l^w=b~|7=
* The page to set. Nl,M9
*/ xQ9P'ru
publicvoid setPage(Page page){ M?Tb9c?`
this.page = page; T_|%nF-+
} '8K5=|!J
} i,1=5@rw5
]/hF!eO
VliX'.-
0B#9CxU%
Y
m=ihQ|
2. 编写业务逻辑接口,并实现它(UserManager, 2jV.\C k
losm<
UserManagerImpl) ma[%,u`
java代码: CRf !tsj@
F]DRT6)
W~(@*H
/*Created on 2005-7-15*/ 7Vd"k;:X
package com.adt.service; Rd@34"O
kIhP 73M
import net.sf.hibernate.HibernateException; GOuBNaU{
U>?q|(u
import org.flyware.util.page.Page; }kzGuNj
u+%Ca,6
import com.adt.bo.Result; /~[+'
$mOVo'2
/** 4^cDp!8
* @author Joa g"aWt%
P
*/ ^F2OTz4n
publicinterface UserManager { $51M'Qu
6t/nM
public Result listUser(Page page)throws P1KXvc}JGe
X- 2 rC
HibernateException; a,g3/
s\i:;`l:=5
} |&OW_*l
|^9+c2
5Z"IM8?
7Mq4$|qhD
q)vdDdRe_
java代码: q-kMqnQ
^Z1t'-xZ
QP/%+[E.
/*Created on 2005-7-15*/ /orpQUHA
package com.adt.service.impl; +c;/hM<IX.
^*JpdmVhu
import java.util.List; C_xOk'091
WeyH;P=
import net.sf.hibernate.HibernateException; ;^+#
8>^(-ca_
import org.flyware.util.page.Page; C><]o
import org.flyware.util.page.PageUtil; .,Qj3
eS)2#=
import com.adt.bo.Result; uG<VQ2LM
import com.adt.dao.UserDAO; W *?mc2;/
import com.adt.exception.ObjectNotFoundException; Tj5G
/H>
import com.adt.service.UserManager; JHQc)@E}
=P'33)
\ )
/** Sc!]M 5
* @author Joa !Rp
*/ W=b<"z]RE
publicclass UserManagerImpl implements UserManager { %B9iby8)1
#m>Rt~(,S
private UserDAO userDAO; :lf;CT6$
$7M/rF;N5X
/** ~DY5`jV
* @param userDAO The userDAO to set. d'j8P
*/ @;>i3?
publicvoid setUserDAO(UserDAO userDAO){ :eIPPh|\
this.userDAO = userDAO; &XG k
} kkWqP20q
w&&uk[Gh/a
/* (non-Javadoc) *;^!FBT
* @see com.adt.service.UserManager#listUser QY14N{]T\p
}{FKs!(4
(org.flyware.util.page.Page) P$l-p'U-
*/ yLv jfP1
public Result listUser(Page page)throws o=/Cje
Twqkd8[
HibernateException, ObjectNotFoundException { !
C}t)R]^
int totalRecords = userDAO.getUserCount(); ^Ej4^d
if(totalRecords == 0) /P_1vQq
throw new ObjectNotFoundException p#-ov-znp
5vxKkk&i4l
("userNotExist"); !%w#h0(b
page = PageUtil.createPage(page, totalRecords); D2hEI2S
List users = userDAO.getUserByPage(page); OPm?kr
returnnew Result(page, users); $xx5+A%,
} 38Rod]\E
$7Sbz&)y3
} #bRr|`
;VQFz&Q$u
JiFy.Pf
W40GW
oL?[9aww
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 t:A,pT3
00DWXGt20o
询,接下来编写UserDAO的代码: $#Mew:J
3. UserDAO 和 UserDAOImpl: "v.]s;g
java代码: P<+y%g(({
m3|KIUP
'Na \9b(
/*Created on 2005-7-15*/ -I, _{3.S
package com.adt.dao; 44s
K2
Y>OL2g
import java.util.List; k:?+75?$
eFO+@
import org.flyware.util.page.Page; $`nKq4Y
T9
@^@l$
import net.sf.hibernate.HibernateException; i?7%z`
{HgW9N(
/** ,!`94{Ggv
* @author Joa ]U :1NC"
*/ p(2j7W-/
publicinterface UserDAO extends BaseDAO { ,H{
/@|RW
K?l1Gj
publicList getUserByName(String name)throws Effp^7 3
F~Kd5-I@
HibernateException; mtfyhFk
to0tH^pD
publicint getUserCount()throws HibernateException; ]mU,y$IQ
0 O{Y
Vk`
publicList getUserByPage(Page page)throws !;Mh5*-
ETu7G5?
HibernateException; !U02>X
KR
} cQ4TYr;?
)G(6=l*
^V^In-[!y:
+MQvq\%tG
*
*?mZtF
java代码: (wJtEoB9^
lYd#pNN
h]Zc&&+8{
/*Created on 2005-7-15*/ Y^dVNC3vd
package com.adt.dao.impl; Q*TxjE7K
m8rz
i:
import java.util.List; 7R\!'`]\M
uo1G
import org.flyware.util.page.Page; Z2chv,SqCJ
uCK!lq-
import net.sf.hibernate.HibernateException; =goZI6 7
import net.sf.hibernate.Query; ?KxI|os
Rl 4r 9
import com.adt.dao.UserDAO; l3aG#4jj
[7Nn%eZC
/** UQ|zSalv,
* @author Joa F"a^`E&
*/ b("JgE`
public class UserDAOImpl extends BaseDAOHibernateImpl YYI
-X@;"0v
implements UserDAO { oeXNb4; 4
3)f=Z2U>
/* (non-Javadoc) (PYUfiOf
* @see com.adt.dao.UserDAO#getUserByName LvpHR#K)F5
=J8)Z'Jr
(java.lang.String) .}fc*2.'
*/ ;{|a~e?Y
publicList getUserByName(String name)throws @C=, >+D
*8p\.za1
HibernateException { M3Kpp_d_!
String querySentence = "FROM user in class IidZ-Il
l,/q#)5[
com.adt.po.User WHERE user.name=:name"; 3&*0n^g
Query query = getSession().createQuery rL URP2~
^F*)Jq
(querySentence); F~d
!Ub$>
query.setParameter("name", name); sF;1)7]Pq
return query.list(); +N[dYm
} ?Di,'
?xf59mY7
/* (non-Javadoc)
Xi5kE'_
* @see com.adt.dao.UserDAO#getUserCount() [ hj|8)
*/ /2u;w!oi.
publicint getUserCount()throws HibernateException { v\Y;)/!
int count = 0; |PN-,f{ -
String querySentence = "SELECT count(*) FROM |xzqYu?o
Coq0Kzhsab
user in class com.adt.po.User"; $2BRi@
Query query = getSession().createQuery EpGe'S
[[D}vL8d
(querySentence); :0T]p"y4
count = ((Integer)query.iterate().next ?HIc=
,|I\{J #C
()).intValue(); We#*.nr{3Z
return count; ^J>28Q\S
} ~E^EF{h
!U`T;\,v5
/* (non-Javadoc) p)ZlQ.d#Y
* @see com.adt.dao.UserDAO#getUserByPage mUy/lo'4
cXJgdBwo
(org.flyware.util.page.Page) jn\\,n"6
*/ IJ,,aCj4g
publicList getUserByPage(Page page)throws VhSKtD1
zi>f436-
HibernateException { ~s^&*KaA
String querySentence = "FROM user in class [ur/`
mC~W/KReA
com.adt.po.User"; B4R,[WE"
Query query = getSession().createQuery `@.YyPxX\
pq5)Ug
(querySentence); e;3$7$n Pv
query.setFirstResult(page.getBeginIndex()) !xo@i XL
.setMaxResults(page.getEveryPage()); \)BKuIP
return query.list(); aic6,>\!'
} {>FA ~}cX.
N5/TV%u
} 0'97af
@YwaOc_%
D~f.)kkC4
-I=}SZ
qUtVqS
至此,一个完整的分页程序完成。前台的只需要调用 XQ(`8Jl&^
D3.sR\Hxf
userManager.listUser(page)即可得到一个Page对象和结果集对象 %n}.E304
BpP\C!:^
的综合体,而传入的参数page对象则可以由前台传入,如果用 !+)$;`
L&3=5Bf9
webwork,甚至可以直接在配置文件中指定。 Tjs-+$P+
uFdSD
下面给出一个webwork调用示例: \((>i7C
java代码: 5!nZvv
wuYo@DDU#
cJ8*[H<NV
/*Created on 2005-6-17*/ xC;$/u%'
package com.adt.action.user; b}"/K$`Fd
0jq&i#yNB
import java.util.List; *)]SsM1
XVv7W5/q]
import org.apache.commons.logging.Log; s?Q`#qD
import org.apache.commons.logging.LogFactory; ]}v`#-Px(
import org.flyware.util.page.Page; rW\~s TH
#-lk=>
import com.adt.bo.Result; [/#n+sz.A
import com.adt.service.UserService; }Xc|Z.6
import com.opensymphony.xwork.Action; CKBi-q FH
M.OWw#?p:_
/** 5h{Hf]A
* @author Joa |e< U %v
*/ +H<%)Lk J
publicclass ListUser implementsAction{ T!a8c<'V
wG{obsL.!
privatestaticfinal Log logger = LogFactory.getLog VGvOwd)E
G,"$Erx
(ListUser.class); 4|+
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w@:o:yLS
private UserService userService; )d.7xY7!
-x_iqrB
private Page page; >8AtT=}w
8dZH&G@;
privateList users; 'xi..
'6WDs]\
/* rLKDeB
* (non-Javadoc) WG}QLcP
* (u'/tNGS
* @see com.opensymphony.xwork.Action#execute() s+CXKb +
*/ 8c/Ii"1
publicString execute()throwsException{ 6nq.~f2`
Result result = userService.listUser(page); =p7W^/c
page = result.getPage(); EEo+#
users = result.getContent(); .A `:o
return SUCCESS; blPC"3}3Vd
} x4( fW\
& {/u>,
/** fzio8mKVX
* @return Returns the page. uBMNkN8
*/ =H?Nb:s
public Page getPage(){ G?_,(
return page; 5g5pzww
} ,pG63&?j
C9iG`?
/** `fV$'u
* @return Returns the users. .z4FuG,R
*/ !*ucVv;
publicList getUsers(){ )I$Mh@F
return users; S8cFD):q
} He*L"VpWv
Z)&HqqT3p
/** a|53E<5X
* @param page ropiyT9;
* The page to set. k %rP*b*
*/ e/3hb)#;
publicvoid setPage(Page page){ $.cGRz
this.page = page; ;Dgp
!*v=
} #P@r[VZ{6
{p\KB!Y-
/** 24Tw1'mW
* @param users n%0vQ;Z1
* The users to set. _t[%@G>P
*/ !Yf0y;e|:
publicvoid setUsers(List users){ l85"C
this.users = users; w#$k$T)
} J|q_&MX/
mNYz7N
/** _L72Ae(_
* @param userService xd.C&Dx5
* The userService to set. wz#n$W3mGf
*/ e+WVN5"ID>
publicvoid setUserService(UserService userService){ )5v .9N6v
this.userService = userService; cA\W|A)
} l{AT)1;^
} KAzRFX),
TDGzXJf[
`ouzeu9}
lq5E?B
Ne EV!V8
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, B;Z^.3
f5-={lUlIS
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 FHC7\#p/9Z
E=QQZ\w
么只需要: (Vv]:Y]
java代码: Ei<:=6EX?8
*S4P'JSY
jYF3u0
)
<?xml version="1.0"?> 5=986ci$U
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork AVWrD[ wD2
. gJKr
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4#9-Z6kOk
jg8P4s
1.0.dtd"> Z#O3s:`
_JDr?Kg
<xwork> PsnU5f)`
C=cTj7Ub
<package name="user" extends="webwork- ~-%A@Lt
QAwj]_
interceptors"> k
N+(
:
eFc.>KoD
<!-- The default interceptor stack name 3\G=J
BxU1Q&
--> K=)R!e8
<default-interceptor-ref DeSTo9A}!
4Ccb!?
name="myDefaultWebStack"/> 5XHkRcESZ
'7R'fhiO/3
<action name="listUser" eV0S:mit
{[?|RC;\Y
class="com.adt.action.user.ListUser"> &/F[kAy
<param qI^jwl|k
-c@ 5qe>
name="page.everyPage">10</param> ;I'/.gW;{
<result nL!@#{z
B vc=gW
name="success">/user/user_list.jsp</result> %5gJ6>@6Z
</action> -pu\p-Z
CK</2 w+
</package> 2A|6o*s"
9(WC#-,
</xwork> KOx#LGz
rg}kxvu
'4sD1LD~}
1_C6KS
gj^]}6-P
NN'<-0~
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 auW]rwY
O$/swwB!
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。 Q%2Lyt"(
z:5ROlk0
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 G{~p.?f:
ooSd6;'
}8:
-I Nj4
:,,y63-f4
%
cdP*
我写的一个用于分页的类,用了泛型了,hoho VH6|(=8
n0pe7/Ai
java代码: VBJ]d|
;i:wY&
@F^L4 N':
package com.intokr.util; #.YcIR)
);DIrA
import java.util.List; `kSCH; mwP
Xy<f_
/** t|QMS M?s
* 用于分页的类<br> !\O,dq
* 可以用于传递查询的结果也可以用于传送查询的参数<br> _ n4ma
* F@bCm+z-
* @version 0.01 K<JP9t6Qd
* @author cheng |qDfFGYf
*/ 6CRPdLTDf
public class Paginator<E> { <h51KPo^P
privateint count = 0; // 总记录数 R7c)C8/~
privateint p = 1; // 页编号 *AR<DXEL
privateint num = 20; // 每页的记录数 -yGm^EwP
privateList<E> results = null; // 结果 1>y=i+T/b
/,Id_TTCO
/** bnu0*Zg>
* 结果总数 gGml
c:/J%
*/ !bQ
&n
publicint getCount(){ F)ld@Ydk=
return count; P.Z<b:V!
} R6mJFE*6T9
r~_ /Jj
publicvoid setCount(int count){ g
'a?
this.count = count; D@W3;T^
} nvVsO>2{ o
3#9r4;&
/** @~G`~8
* 本结果所在的页码,从1开始 HCkqh4
* $!!=fFX*y
* @return Returns the pageNo. [<a%\:c m4
*/ c.A/{a
publicint getP(){ b\m(0/x
return p; kdPm # $-
} w!w _`7[
6FIoWG"x
/** "gajBY
* if(p<=0) p=1 8A u<\~p
* ND1%s &
* @param p g4SYG)'R+
*/ Yf)|ws?!
publicvoid setP(int p){ k:)u7A+
if(p <= 0) LEnP"o9ZW
p = 1; 7h&`BS
this.p = p; =1OAy`8
} E(kb!Rz
p<fgUVR
/** 7"NJraQ6
* 每页记录数量 :fKz^@mY4
*/ YkAWKCOni
publicint getNum(){ `Mp7})
return num; M#=5u`h
} ~2DV{dyj
a;T[%'in
/** y{I[}$k
* if(num<1) num=1 8 E+C:"
*/ [Pc[{(
publicvoid setNum(int num){ $SGA60q
if(num < 1) o/9LK
num = 1; 53*, f
this.num = num; 7RC096 ?}
} Il`k]X M
"mK i$FV
/** o``>sBZOq
* 获得总页数 /A))"D
*/ rjQhU%zv
publicint getPageNum(){ +ls*//R
return(count - 1) / num + 1; :tqm2t
} x`6^+>y^
Sc$8tLDLj
/** -@V"i~g<e
* 获得本页的开始编号,为 (p-1)*num+1 !5SQN5K
*/ )Z]y.W )
publicint getStart(){ 6?.pKFBZ
return(p - 1) * num + 1; u#@{%kPW
} HGQ?(2] 8$
^8l3j4
/** 3?Eoj95w!
* @return Returns the results. $gl<{{
*/ #!u51P1
publicList<E> getResults(){ SP?U@w%}
return results; V]kGcS}
} u}LX,B-n(
m5em<P!G
public void setResults(List<E> results){ ]v\egfW,W
this.results = results; j5h
6u,^:
} dJ%Rk#?;A
M$4=q((0
public String toString(){ ~z
_](HKoS
StringBuilder buff = new StringBuilder @?7{%j*
3JZWhxkf[$
(); {+6D-rDw
buff.append("{"); V>j hGf
buff.append("count:").append(count); PSf5p\<5
buff.append(",p:").append(p); DMcxa.Sd!
buff.append(",nump:").append(num); [kuVQ$)
buff.append(",results:").append YyJ{
Z'*Z@u3
(results); 7kX$wQZ_
buff.append("}"); YaNH.$.:
return buff.toString(); #W%)$kc
} vuo'"^ =p0
)x8;.@U
} Ds%&Mi
sId(PT^
uQu/(5