Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 uE;bNs'
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 R?Dc*,
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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 X+$IaLfCxD
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 y~r5KB6w
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分页支持类: p~evPTHnrX
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java代码: qX%oLa
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package com.javaeye.common.util; yh'uH
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import java.util.List; "C~Zl&3
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publicclass PaginationSupport { @
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publicfinalstaticint PAGESIZE = 30; >u0B ~9_E
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privateint pageSize = PAGESIZE; )wb&kug-
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privateList items; _@/nc:)H
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privateint totalCount; sWGc1jC?.F
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privateint[] indexes = newint[0]; fgW>~m.W
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privateint startIndex = 0; B*AF8wX|
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public PaginationSupport(List items, int Q|]
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totalCount){ ^!j,d_)b!
setPageSize(PAGESIZE); huTWoMU
setTotalCount(totalCount); n ]<>$
setItems(items); Xf/qUao
setStartIndex(0); _Z0O]>KH
} tXg>R _\C
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public PaginationSupport(List items, int mNDd>4%H_
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totalCount, int startIndex){ g54b}vzm
setPageSize(PAGESIZE); 1R"?X'w
setTotalCount(totalCount); H]<@\g*l@P
setItems(items); >J['so2Bf
setStartIndex(startIndex); RK\$>KFE
} nN*:"F/^
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public PaginationSupport(List items, int }}q_QD_
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totalCount, int pageSize, int startIndex){ k%TjRf{p
setPageSize(pageSize); ^ - H
setTotalCount(totalCount); hTS?+l
setItems(items); [39
setStartIndex(startIndex); [R%Pf/[Fr
} Ra-%,cS
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publicList getItems(){ .DN)ck:e;
return items; Y| 2Gj(*8
} gQ;1SY!
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publicvoid setItems(List items){ 0NFYFd-50
this.items = items; UgC{
} gBPYGci2F
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publicint getPageSize(){ ? f>pKe
return pageSize; 2J1YrHj3
} /xh/M@G3
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publicvoid setPageSize(int pageSize){ -8pQI
this.pageSize = pageSize; dOx0'q"Z
} /^9K Zj
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publicint getTotalCount(){ yRtxh_wr9
return totalCount;
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} T^1]|P
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publicvoid setTotalCount(int totalCount){ 89+Q^79m
if(totalCount > 0){ &
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this.totalCount = totalCount;
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int count = totalCount / =1e>$E#
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pageSize; 9yWQ}h
if(totalCount % pageSize > 0) >j}.~$6dj_
count++; _I
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indexes = newint[count]; J<27w3bs~p
for(int i = 0; i < count; i++){ 79G& 0 P\
indexes = pageSize * [~UCYYl
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} w^N3Ma
}else{ s;!Tz)
this.totalCount = 0; T$vDw|KSVP
} -V'h>K
} (I0QwB
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publicint[] getIndexes(){ ]<g`rR7}
return indexes; t/Y)% N
} xa]e9u%
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publicvoid setIndexes(int[] indexes){ )a0%62
this.indexes = indexes; ! 1wf/C;=
} I]vCra
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publicint getStartIndex(){ :o=a@Rqx
return startIndex; )D>= \Me
} 5 4vDP 9
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publicvoid setStartIndex(int startIndex){ S :%SarhBD
if(totalCount <= 0) *fg|HH+i
this.startIndex = 0; BELxaV,
elseif(startIndex >= totalCount) SM1[)jZ-
this.startIndex = indexes XPd@>2
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[indexes.length - 1]; _+NM<o#A
elseif(startIndex < 0) YfZ96C[a
this.startIndex = 0; f>kW\uC
else{ EI!e0V1!
this.startIndex = indexes f.Feo
8-uRn38
[startIndex / pageSize]; Y>i5ubR~
} 6>R|B?I%
} 9aKt (g6
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publicint getNextIndex(){ ml\2%07
int nextIndex = getStartIndex() + ,,o5hD0V9
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pageSize; Jh!'"7
if(nextIndex >= totalCount) pon0!\ZT=
return getStartIndex(); wr{ [4$O
else K! e51P
return nextIndex; Ubf@"B
} '3eL^Aq
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publicint getPreviousIndex(){ lJ$j[Y
int previousIndex = getStartIndex() - 1C]mxV=%
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pageSize; Tn"/EO^N
if(previousIndex < 0) T2p;#)dP
return0; }[c,/NH
else 8DO3L
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return previousIndex; ;[R#:Rk
} [Z$E^QAP
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} 2SHS!6:Rl
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抽象业务类 QxS=W2iN
java代码: Qqn9nO9
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/** w/UZ6fu
* Created on 2005-7-12 3qNLosm#M
*/ (// f"c]/
package com.javaeye.common.business; Gr}lr gP S
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import java.io.Serializable; hCFgZiH2
import java.util.List; [8$K i$;
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import org.hibernate.Criteria; M#a1ev
import org.hibernate.HibernateException; 1xsIM'&
import org.hibernate.Session; s%xhT
import org.hibernate.criterion.DetachedCriteria;
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import org.hibernate.criterion.Projections; 6L4<c+v_
import || 0n%"h>i
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org.springframework.orm.hibernate3.HibernateCallback; K|^'`FpPO
import /@qnEP%
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org.springframework.orm.hibernate3.support.HibernateDaoS U,e'vS{
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upport; LzE$z,
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import com.javaeye.common.util.PaginationSupport; `%oJa`
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public abstract class AbstractManager extends 5wgeA^HE2y
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HibernateDaoSupport { G>f2E49BXt
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privateboolean cacheQueries = false; >uR0Xs;V
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privateString queryCacheRegion; %S9YjMR@
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publicvoid setCacheQueries(boolean uW4wTAk;qh
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cacheQueries){ }X?M6;$)
this.cacheQueries = cacheQueries; wcW8"J'AH
} (eEs0
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publicvoid setQueryCacheRegion(String Tc.k0n%W:b
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queryCacheRegion){ ) u
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this.queryCacheRegion = .XTR
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queryCacheRegion; Al-;-t#Dc
} @B#\3WNt
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publicvoid save(finalObject entity){ n4%ZR~9WH
getHibernateTemplate().save(entity); (Xv'Te?
} 4SDUTRoa
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publicvoid persist(finalObject entity){ 9?J
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getHibernateTemplate().save(entity); _`- trE.
} ,C97|6rC
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publicvoid update(finalObject entity){ jqv"8S5
getHibernateTemplate().update(entity); MFzJ 8^.1R
} b;k3B7<
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publicvoid delete(finalObject entity){ e:uk``\
getHibernateTemplate().delete(entity); B/F6WQdZ
}
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publicObject load(finalClass entity, 1~aP)q
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finalSerializable id){ ~4^~w#R
return getHibernateTemplate().load =&~7Q"
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(entity, id); vOQ
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} l2Pry'3
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publicObject get(finalClass entity, 8gn12._x
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finalSerializable id){ qSA]61U&
return getHibernateTemplate().get l.nd Wv
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(entity, id); 5x? YFq6k
} xmXuBp:M(R
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publicList findAll(finalClass entity){
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return getHibernateTemplate().find("from w]O[{3"
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" + entity.getName()); UI%Z`.&
} $s]vZ(H
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publicList findByNamedQuery(finalString B9(@.
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namedQuery){ OC=g 1
return getHibernateTemplate `p'682x I
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().findByNamedQuery(namedQuery); `~k`m{4.a
} 6Q*Zy[=
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publicList findByNamedQuery(finalString query, \`U=pZJ
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finalObject parameter){ N}gPf
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return getHibernateTemplate Ek6z[G`
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().findByNamedQuery(query, parameter); "K c/Cs2[
} v|Y
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publicList findByNamedQuery(finalString query, \)`OEGdOR\
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finalObject[] parameters){ L6x;<gj
return getHibernateTemplate |}><)}
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().findByNamedQuery(query, parameters); G_]zymXQ
} SceK$
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publicList find(finalString query){ XY^]nm-{I
return getHibernateTemplate().find "IN[(
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(query); $W]}m"l
} R8-=N+hX
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publicList find(finalString query, finalObject BUS4 T#D
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parameter){ =Hbf()cN)
return getHibernateTemplate().find Ozg,6&3ji
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(query, parameter); ,@kLH"a0
} 0bG#'.-
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public PaginationSupport findPageByCriteria <?>tjCg'
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(final DetachedCriteria detachedCriteria){ "`NAg
return findPageByCriteria 7M)<Sv
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); eLIZ<zzW0}
} ,N1pw w?
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public PaginationSupport findPageByCriteria #mYe@[p@
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(final DetachedCriteria detachedCriteria, finalint $R%tD.d3
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startIndex){ K@%gvLa\
return findPageByCriteria (&SPMhs_|(
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(detachedCriteria, PaginationSupport.PAGESIZE, 5"y)<VLJX
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startIndex); $*`E;}S0
} l9e=dV:pH
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public PaginationSupport findPageByCriteria Q zg?#|
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(final DetachedCriteria detachedCriteria, finalint Zv2]X-
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pageSize, 4V c``Um
finalint startIndex){ j\"d/{7Q
return(PaginationSupport) P_5 G'[
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getHibernateTemplate().execute(new HibernateCallback(){ (|#%omLL
publicObject doInHibernate Kn1T2WSAg
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(Session session)throws HibernateException { I:w+lchAMe
Criteria criteria = 6VS_L@
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detachedCriteria.getExecutableCriteria(session); 2I|lY>Z
int totalCount = 97 ,Y q3
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((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); I2krxLPd
criteria.setProjection 0dQ\Y]b
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(null); i9V,
List items = c$lZ\r"
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criteria.setFirstResult(startIndex).setMaxResults Q+/P>5O/
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(pageSize).list(); :Gzp
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PaginationSupport ps = kkW }:dBl
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new PaginationSupport(items, totalCount, pageSize, }#2(WHf=<
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startIndex); 8C?E1fH\
return ps; .|Yn[?(
} p>f?Rw_
}, true); I0><IaFy
} fQwLx
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public List findAllByCriteria(final -r]L MQ
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DetachedCriteria detachedCriteria){ x<OVtAUB
return(List) getHibernateTemplate
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().execute(new HibernateCallback(){ gyPwNE
publicObject doInHibernate m.\JO
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(Session session)throws HibernateException { |f\WVGH
Criteria criteria = 4?+jvVq
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detachedCriteria.getExecutableCriteria(session); dPxJ`8
return criteria.list(); xZM4CR9]*C
} #_|O93HN'
}, true); O4:_c-V2
} uRYq.`v,
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public int getCountByCriteria(final ~w9`l8/0
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DetachedCriteria detachedCriteria){ gIIF17|Z
Integer count = (Integer) 7TU xdI
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getHibernateTemplate().execute(new HibernateCallback(){ 1*'gaa&y
publicObject doInHibernate 9g'6zB
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(Session session)throws HibernateException { BjfTt:kY
Criteria criteria = |7 Ab_
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detachedCriteria.getExecutableCriteria(session); E cSu[b
return A0,e3gb
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criteria.setProjection(Projections.rowCount XX
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()).uniqueResult(); Eau
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} +?[s"(
}, true); )>^ Ge9d]
return count.intValue(); ]"htOO
} \rg;xZa5
} ?<5KLvG v
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用户在web层构造查询条件detachedCriteria,和可选的 94]i|2qj*
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 XW\
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PaginationSupport的实例ps。 %o0 H#7'
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ps.getItems()得到已分页好的结果集 c,M"a
ps.getIndexes()得到分页索引的数组 t<$J
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ps.getTotalCount()得到总结果数 3+
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ps.getStartIndex()当前分页索引 wehiX7y
ps.getNextIndex()下一页索引 Twr,O;*u=
ps.getPreviousIndex()上一页索引 Kb-m
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 I)0_0JXs
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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 -^;,m=4{3
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一下代码重构了。 y@7CY-1
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我把原本我的做法也提供出来供大家讨论吧: Bn=YGEvz
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首先,为了实现分页查询,我封装了一个Page类: .3@Pz]\M#>
java代码: PlT_]p
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/*Created on 2005-4-14*/ Uyeo0B"
package org.flyware.util.page; Y?zo")
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/** tK'9%yA\
* @author Joa qSD3]Dv"
* B<$6Dj%L
*/ -%K}~4J
publicclass Page { &%k_BdlkQ
(?lT @RY/
/** imply if the page has previous page */ yJlRW!@&:
privateboolean hasPrePage; RyM29uD
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/** imply if the page has next page */ FL&Y/5
privateboolean hasNextPage; =^l`c$G<
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/** the number of every page */ `krVfE;_O
privateint everyPage; 8YgRJQZ!
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/** the total page number */ oz[G'[\}F
privateint totalPage; bxBndxl
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/** the number of current page */ cS@p`A7Tpo
privateint currentPage; -Ekf T_
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/** the begin index of the records by the current %.Kr`#lCr
3/(eK%d4Xb
query */ &_j<!3*
privateint beginIndex; *YX:e@Fm.a
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/** The default constructor */ ed3wj3@
public Page(){ %\)AT"
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} / T_v8{D
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/** construct the page by everyPage EaH/Gg3
* @param everyPage hw)z]
* */
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public Page(int everyPage){ +bb-uoZf
this.everyPage = everyPage; wqap~X
} ;vWJOvM2
{ ~(XO@;b
/** The whole constructor */ -rHqU|
public Page(boolean hasPrePage, boolean hasNextPage, fZJM'+J@A
77 Z:!J|
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int everyPage, int totalPage, |RqCI9N6
int currentPage, int beginIndex){ U^DR'X=
this.hasPrePage = hasPrePage; YdB/s1|G
this.hasNextPage = hasNextPage; MI.OOoP3a
this.everyPage = everyPage; U_E t
this.totalPage = totalPage; i3Xo6!Q
this.currentPage = currentPage; AP4s_X+=
this.beginIndex = beginIndex; :`<MlX
} T8W^qrx.v
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/** Z *v`kl
* @return %N\8!aXnf
* Returns the beginIndex. ) :Px`] 5
*/ f'qM?GlET
publicint getBeginIndex(){ lR`.V0xA
return beginIndex; /7Q9(}
} 8|+@A1)&4
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/** kK0zb{
* @param beginIndex 9'|_1Q.b^
* The beginIndex to set. J%!vhQ
*/ 9J<vkxG9`
publicvoid setBeginIndex(int beginIndex){ IEI&PRD
this.beginIndex = beginIndex; C*t0`3g
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} ~4] J'E >
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n`).
/** `}a-prT<f
* @return u%OLXb
* Returns the currentPage. #H5+8W
*/ 77]lpmC
publicint getCurrentPage(){ tZ*>S]qD
return currentPage; 8k.#4}fP
} "tDB[?
r $ YEq5
/** )2u_[Jc=
* @param currentPage UjyrmQf
* The currentPage to set. +vV?[e
*/ 0[8uuqV[cB
publicvoid setCurrentPage(int currentPage){ fN9uSnu
this.currentPage = currentPage; TIF =fQ
} Wi~?2-!
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/** {"rL3Lk
* @return [8 23w.{]#
* Returns the everyPage. U0N6\+
*/ ;:Tb_4Hr
publicint getEveryPage(){ 8\PI1U
return everyPage; b/E3Kse?
} *hpS/g/3\
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/** ndk~(ex|j
* @param everyPage &7{yk$]*
* The everyPage to set. zIr-Rx'dL^
*/ 5)->.* G*
publicvoid setEveryPage(int everyPage){ X8~?uroq
this.everyPage = everyPage; qmNG|U&
} ="AaC!E,W
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/** OhM_{]*
* @return tvUC d}
* Returns the hasNextPage. vJX0c\e
*/ e YiqT Wn:
publicboolean getHasNextPage(){ w(*},
return hasNextPage; T]\'D&P~D
} YjPj#57+
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/** _d>{Hz2
* @param hasNextPage n9Vr*RKM)
* The hasNextPage to set. `y{[e j
*/ `@So6%3Y|
publicvoid setHasNextPage(boolean hasNextPage){ ws$kwSHq
this.hasNextPage = hasNextPage; 8LY^>.
} )d{fDwrx1
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/** X"jtPYCpV{
* @return 7b8y
* Returns the hasPrePage. :g+wv}z
*/ {.Brh"yC
publicboolean getHasPrePage(){ I(z16wQ
return hasPrePage; on1B~?*D
} bu=RU
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/** 4lwoTGVZj
* @param hasPrePage x((Rm_'
* The hasPrePage to set. ghTue*A
*/ VWk{?*Dp
publicvoid setHasPrePage(boolean hasPrePage){ 0="wxB
this.hasPrePage = hasPrePage; m@",Zr`f=
} {9cjitl
_KZTY`/*
/** uSH_=^yTQ
* @return Returns the totalPage. tCv}+7)
* F4IU2_CnPD
*/ )`mBvS.}
publicint getTotalPage(){ Sf2xI'
return totalPage; %Y9CZRY9
} vX&W;&
/*t H$\6*
/** l]~IZTC
* @param totalPage :*YnH&
* The totalPage to set. n(sseQ|\
*/ \Qf2:[-V0
publicvoid setTotalPage(int totalPage){ W<$!H
V$
this.totalPage = totalPage; s?
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} :BB=E'293
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} HI,`O
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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 $ <3^( y
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个PageUtil,负责对Page对象进行构造: -wh
java代码: ,E"n 7*6mr
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/*Created on 2005-4-14*/ F
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package org.flyware.util.page; W>'(MB$3
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import org.apache.commons.logging.Log; `A-
import org.apache.commons.logging.LogFactory; FuG;$';H75
` }B,w-,io
/** ')Y1cO
* @author Joa e$&n)>%
* 5<P6PHdY
*/ 5=8t<v1Bn
publicclass PageUtil { 8isQL
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privatestaticfinal Log logger = LogFactory.getLog g8@F/$HY
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(PageUtil.class); FrE#l.)?!
!'B='].
/** gMp' S
* Use the origin page to create a new page oN`khS]_v0
* @param page R*r"};
* @param totalRecords Pc<0kQg
* @return \s!x;nw[
*/ pF(6M3>IN
publicstatic Page createPage(Page page, int :>F3es`
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q
totalRecords){ Y~?Z'uR
return createPage(page.getEveryPage(), Pz0TAb
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page.getCurrentPage(), totalRecords); <(H<*Xf9
} UD9JE S,
}daU/
/** &xp]9$
* the basic page utils not including exception ?Cx=!k.
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handler =|2F?
* @param everyPage h\Q@zR*0a
* @param currentPage y>)c?9X
* @param totalRecords W Bb*2
* @return page z;_vl
*/ S#<y_w%
publicstatic Page createPage(int everyPage, int qW'L}x
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currentPage, int totalRecords){ #%w)w R3
everyPage = getEveryPage(everyPage); Z]x6np
currentPage = getCurrentPage(currentPage); mI]gDL1
int beginIndex = getBeginIndex(everyPage, ? % A2
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currentPage); c2?VjuB0
int totalPage = getTotalPage(everyPage, y~su1wUp
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totalRecords); *z.rOY=
8
boolean hasNextPage = hasNextPage(currentPage, }D.\2x(J
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totalPage); 9,JWi{lIv
boolean hasPrePage = hasPrePage(currentPage); Et0)6^-v
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returnnew Page(hasPrePage, hasNextPage, $PAAmaigi
everyPage, totalPage, !Ce!D0Tx
currentPage, sZ;Gb^{Z
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beginIndex); ]Qa|9G,b
} E0yx
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privatestaticint getEveryPage(int everyPage){ D@:'*Z(
return everyPage == 0 ? 10 : everyPage; _pDfPLlY&
} dCo3 VF"u
pM}~/
privatestaticint getCurrentPage(int currentPage){ 3s67)n
return currentPage == 0 ? 1 : currentPage; <]X6%LX
} 9X
+dp
=;E0PB_w
privatestaticint getBeginIndex(int everyPage, int 9!kp3x/`
4nGt*0Er
currentPage){ Uw!d;YQm
return(currentPage - 1) * everyPage; Y=g]\%-PB
} h=JW^\?\]
>5?:iaq
z
privatestaticint getTotalPage(int everyPage, int 7[UD;&\k
q]VB}nO
totalRecords){ 5G$ ,2i(
int totalPage = 0; "z;R"sv\
~"<^4h
if(totalRecords % everyPage == 0) |lZp5MOc
totalPage = totalRecords / everyPage; !2^~ar{2
else )Y9\>Xj7
totalPage = totalRecords / everyPage + 1 ; 5 jUy[w @
D$*o}*mb
return totalPage; 8R:Glif
} 1N:~5S}s>
= ^Vp \
privatestaticboolean hasPrePage(int currentPage){ 6(uZn=
return currentPage == 1 ? false : true; wG9aX*(n
} 9qgs*]J
+|7N89l
privatestaticboolean hasNextPage(int currentPage, +!!G0Zj/
K+XUC
int totalPage){ %5DM ew
return currentPage == totalPage || totalPage == d3S Me
]61HQ
0 ? false : true; T,rRE7
} ~8"oH5
#NYHwO<0-
';c 6
} ?Zsh\^k.g
8 H3u"
kFC*,
nc\2A>f`
0:<Y@#L
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 +."cbqGP_q
k_ywwkG9lU
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Cb`, N
~G-W|>
做法如下: 9 wbQ$>G9
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0fn*;f8{XJ
K"&^/[vMB
的信息,和一个结果集List: 2|d^#8)ZC
java代码: F&m9G >r
WSN^iDS
9V[}#(f$
/*Created on 2005-6-13*/ gIusp917
package com.adt.bo; 0@{0#W3R
@rDBK] V
import java.util.List; *|<~IQg
&;)B
qqXc
import org.flyware.util.page.Page; K~I?i/P=z
dr+(C[=
/** vt^7:!r
* @author Joa sQ,xTWdj
*/ LExm#T`
publicclass Result { !{+.)%d'g
'`.-75T
private Page page; v9Sk\9}S
32?'jRN(ue
private List content; / o
I 4&W
JbS[(+o
/** O9/)_:Wdh
* The default constructor .{*l,
*/ M\
public Result(){ -!\%##r7~
super(); G
&NK
} ZfH>UHft
8ih_S2Cd
/** D7JrGaF{
* The constructor using fields $u'"C|>8
* *Egg*2P;"Q
* @param page L8!yP.3
* @param content 9H/R@i[E
*/ v}a{nU'
public Result(Page page, List content){ ~:o$}`mW
this.page = page; 'SoBB:
this.content = content; 5`+9<8V
} dE_"|,:
)h&@}#A09
/** (dD7"zQ
* @return Returns the content. .%e>>U>F
*/ ~<9e}J
publicList getContent(){ la w$LL
return content; kp* !
} JGTsVa2
SA&(%f1d
/** naH(lz|v
* @return Returns the page. %.r\P@7/Q
*/ fCF.P"{W"
public Page getPage(){ X&LJ"ahK
return page; f\_PNZCc
} qlYi:uygY
{FKr^)g
/** *fIn<Cc
* @param content Skg/iH"(
* The content to set. D&2NO/
R
*/ o{fYoBgr
public void setContent(List content){ o:W*#dt
this.content = content; Qg~w 3~
} s(5hFuyg
;CF:cH*
/** *pSnEWwE
* @param page W&R67ff|
* The page to set. @48!e-W
*/ +$nNYD
publicvoid setPage(Page page){ uax0%~O\
this.page = page; `iM%R3&
} l&U$LN$*e
} 0m4M@94
OG?7(
UJ
+h+ 7Q'k
tP*Kt'4W
8>#ZU]cG
2. 编写业务逻辑接口,并实现它(UserManager, GdNhEv
rf4f'cUa
UserManagerImpl) $w{d4" )
java代码: 'uDx$AkY
Ui
(nMEon
Fj~suZ`
/*Created on 2005-7-15*/ %aMC[i
package com.adt.service; G$V=\60a-
`x#S.b
import net.sf.hibernate.HibernateException; .24z+|j
av|T|J/(
import org.flyware.util.page.Page; FGHCHSqLq
2&n6:"u|
import com.adt.bo.Result; f7\X3v2W}3
O!f37n-TB
/** 4c 8{AZ
* @author Joa l1'v`!
*/ k)*apc\W
publicinterface UserManager { =Q<7[
+
c3pe4
public Result listUser(Page page)throws *->*p35
mHW%:a\L
HibernateException; Gt*K:KT=L
0Atha>w^o~
} _v 0iH
E] /2u3p
.x,y[/[[)
OzrIiahz/
u%z'.#r; a
java代码: (XmmbAbVom
b/
\EN)
;#9?3Os
/*Created on 2005-7-15*/ 6P717[
package com.adt.service.impl; DMG'8\5C
.Vnb+o
import java.util.List; ~ E6e~
-i{_$G8W/c
import net.sf.hibernate.HibernateException; v9Ii8{ca|
dt"/4wCO
import org.flyware.util.page.Page; i56Rdb
import org.flyware.util.page.PageUtil; %|}*xMQ
uuwJ-
import com.adt.bo.Result; kOD=H-vSi
import com.adt.dao.UserDAO; W g7
eY'FE
import com.adt.exception.ObjectNotFoundException; VED~v#.c
import com.adt.service.UserManager; ;BH.,{*@B
3\j`g
/** 4sQm"XgE
* @author Joa '=Zm[P,
*/ ?<3 d
Fb
publicclass UserManagerImpl implements UserManager { ;6pB7N
):>?N`{V
private UserDAO userDAO; k6ry"W3
o^X3YaS)
/** 9|<Li[
* @param userDAO The userDAO to set. KqJln)7
*/ Lr:n
publicvoid setUserDAO(UserDAO userDAO){ B//*hH >F
this.userDAO = userDAO; bHRn}K+<}c
} xJ{r9~
W;7$Dq:
/* (non-Javadoc) mwLf)xt0'
* @see com.adt.service.UserManager#listUser PbZ%[F
WFahb3kx
(org.flyware.util.page.Page) yXDjM2oR/2
*/ +%\Ci!%b
public Result listUser(Page page)throws {v]L|e%{
B3&C&o.h
HibernateException, ObjectNotFoundException { ddKP3}
int totalRecords = userDAO.getUserCount(); BT8)t.+pv
if(totalRecords == 0) N7lg6$s Aj
throw new ObjectNotFoundException ^_@[1'^
ANBuX6q
("userNotExist"); Oo;]j)z
page = PageUtil.createPage(page, totalRecords); &Hp*A^M
List users = userDAO.getUserByPage(page); rrRv 7J&Q
returnnew Result(page, users); `WL3aI":
} hO$Gx*e$
zCo$YP#5_
} bLG7{qp
])F+ C/Px1
B7'#8heDh
$%bd`d*S
F*J1w|)F0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,v})
q&>fKS nKs
询,接下来编写UserDAO的代码: 1O0. CC,p
3. UserDAO 和 UserDAOImpl: G) KI{D
java代码: |s/N?/qi
Nkj$6(N=zJ
U"8Hw@
/*Created on 2005-7-15*/ #2%V
package com.adt.dao; W|fE]RY
h.#:7d(g
import java.util.List; 8Snv, Lb`^
A+Isk{d
import org.flyware.util.page.Page; C=o-3w
,i}EGW,9q
import net.sf.hibernate.HibernateException; M| Gl&
hR|xUp
/** \\:%++}J
* @author Joa 5`fUR/|[
*/
zo@vuB.
publicinterface UserDAO extends BaseDAO { vv,<#4d
Z ;rM@x
publicList getUserByName(String name)throws H*k\C
KH?6O%d
HibernateException; }[z7V
sz270k%[
publicint getUserCount()throws HibernateException; U=KUx
!5De?OXe
publicList getUserByPage(Page page)throws
\8C<nh
#n+u>x.O
HibernateException; iYT?6Y|+
)tJaw#Mih
} !Ltx2CB2]
t^MTR6y+8
AcnY6:3Y|
YFu,<8"swe
bi}aVtG~z
java代码: dF51_Kk
~;$QSO\2h
&1T)'Bn
/*Created on 2005-7-15*/ 3xz~##
package com.adt.dao.impl; W"@'}y
~fD\=- S1
import java.util.List; 5SUO`4L
'6NrL;
import org.flyware.util.page.Page; RICm$,
M.dX;iM<
import net.sf.hibernate.HibernateException; EgPL+qL
import net.sf.hibernate.Query; ~Sb)i f
g#74c'+
import com.adt.dao.UserDAO; REU&8J@k&?
VOr:G85*s
/** ~tfd9,t
* @author Joa 3s%DF,
*/ ef7 U7
public class UserDAOImpl extends BaseDAOHibernateImpl "aKlvK:77
.u
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implements UserDAO { Y5C kC F
\8ZVI98
/* (non-Javadoc) A/a=)su
* @see com.adt.dao.UserDAO#getUserByName CB>W# P%
(|AZO!
(java.lang.String) X(E`cH
|
*/ u8JH~b
publicList getUserByName(String name)throws _y6iR&&x
UmpHae
HibernateException { \41/84BA
String querySentence = "FROM user in class .9ZK@xM&?
8*b{8%<K
com.adt.po.User WHERE user.name=:name"; 2dHO!A$RF
Query query = getSession().createQuery I@VzH(da\
7t<h 'g2
(querySentence); khR[8j..
query.setParameter("name", name); .53 M!
return query.list(); nl(GoX$vRQ
} 4=^Ha%l
bnL!PsG$K,
/* (non-Javadoc) 4|%Y09"lv
* @see com.adt.dao.UserDAO#getUserCount() q90RTX'CY
*/ xC9?rLUZ
publicint getUserCount()throws HibernateException { O{3X`xAf
int count = 0; ]Kjt@F";
String querySentence = "SELECT count(*) FROM 8dx7@y?z
b/oNQQM#Dk
user in class com.adt.po.User"; 5V(#nz
Query query = getSession().createQuery dKEy6C"@
w2b(,w
(querySentence); (5Q<xJ
count = ((Integer)query.iterate().next RgH 6l2
v9@_DlV\
()).intValue(); Lbrn8,G\
return count; (FGy"o%TP'
} onmkg}&_
E71H=C 4
/* (non-Javadoc) @^ta)Ev
* @see com.adt.dao.UserDAO#getUserByPage .,'4&}N}
_VgFuU$h
(org.flyware.util.page.Page) o@PvA1
*/ !!ZGNZ_
publicList getUserByPage(Page page)throws v]@ XyF\j8
oVP,ar0G
HibernateException { T[e+iv<8j
String querySentence = "FROM user in class sF :pwI5^
g2?W@/pa
com.adt.po.User"; &?p(UY7'"
Query query = getSession().createQuery b-VQn5W
Q~f]?a`
(querySentence); @b 17jmq{
query.setFirstResult(page.getBeginIndex()) p)Q5fh0-
.setMaxResults(page.getEveryPage()); )Z4iM;4]
return query.list(); $; _{|{Yj
} r@i)Sluf
0#Us*:[6
} *uK!w(;2
i4> M
DU,B
;m|N9'
p"6[ S
至此,一个完整的分页程序完成。前台的只需要调用 lBG=jOS
xa_ IdkV
userManager.listUser(page)即可得到一个Page对象和结果集对象 wO!>kc<
Av n-Ug
的综合体,而传入的参数page对象则可以由前台传入,如果用 QYDI-<.(
p; , V
webwork,甚至可以直接在配置文件中指定。 ZB$yEW]]~
6IK>v*<
下面给出一个webwork调用示例: Z?[R;V1j
java代码: u&={hJ&7
>_]Ov:5
# ^,8JRA
/*Created on 2005-6-17*/ /8:e|
]
package com.adt.action.user; +6+1N)L
Sa)L=5Nr
import java.util.List; Z{%W!>0
kda*rl~c
import org.apache.commons.logging.Log; u#u/uS"
import org.apache.commons.logging.LogFactory; IAb.Z+ig
import org.flyware.util.page.Page; c"CR_
i,RbIZnJ
import com.adt.bo.Result; PQF
40g1}
import com.adt.service.UserService; qD"~5vtLqQ
import com.opensymphony.xwork.Action; )Mflt0fp
NODg_J~T
/** 4\V/A+<W
* @author Joa OiC|~8
*/ N1y,~Z
publicclass ListUser implementsAction{ I
WT|dA >
Oel%lY}m3
privatestaticfinal Log logger = LogFactory.getLog _a$5"
pox;NdX7
(ListUser.class); Wo9=cYC)
ia.+<,
$`S
private UserService userService; uJ1oo| sn
nWf8r8
private Page page; 9"Dt3>Z
ESIeZhXVH
privateList users; $*XTX?,'
8&+u+@H
/* l%i*.b(
* (non-Javadoc) ?a,`{1m0\
* xjxX4_
* @see com.opensymphony.xwork.Action#execute() Om7 '_}
*/ E\Iz:ES^
publicString execute()throwsException{ 1"<{_&d1
Result result = userService.listUser(page); meap ;p
page = result.getPage(); S n~P1C
users = result.getContent(); 9zBt
a
return SUCCESS; g[ @Q iy
} D7thLqA
ei]Q<vT6
/** VJr ~h
"[
* @return Returns the page. \:JY[s/
*/ "K|':3n|
public Page getPage(){ Bbb":c6w0
return page; :$X dR:f}}
} K`|V1L.m
\\oa[nvL~
/** JAwEu79sh
* @return Returns the users. w17{2']
*/ "yU<X\ni
publicList getUsers(){ X2np.9hie
return users; /bC@^Y&}
} ja{x}n*5
}Vm'0
/** g+&wgyq5
* @param page 8_rd1:t5
* The page to set. jW| ,5,43
*/ ?^8.Sa{
publicvoid setPage(Page page){ 0+_;6
this.page = page; {FC<vx{42
} Q"LlBp>t|#
S@,x^/vT
/** $S/WAw,/
* @param users !.q#X^@>L
* The users to set. wv%UsfD
*/ 0*uJS`se6Z
publicvoid setUsers(List users){ ^zG!Z:E
this.users = users; IMy!8$\u
} "zIQ(|TL?d
)4YtdAV
/** 6UPGE",u
* @param userService 6iH]N*]S^
* The userService to set. etb#/L
*/ W,t`DMC
publicvoid setUserService(UserService userService){ yS#D$q2_
this.userService = userService; 5RSP.Vyx{
} `;Fs
} TPZ^hL>ao
4]cr1K
^
D_w<igu!3
`V[ hE
r|
q^[SN
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 0|rdI,z
PXDJ[Oj7(0
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ,;=is.h9
<z
wI@i
么只需要:
<j_
java代码: gX5.u9%C\
[s-!tE3-
{]y!2r
<?xml version="1.0"?> #vcQ =%;O
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Ei@al>.\
URyY^+s
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 8vvNn>Q
DeN$YE#*
1.0.dtd"> -K5u5l}
DCCij N
<xwork> s*kSl:T@O
aQ1n1OBr
<package name="user" extends="webwork- \AD|;tA\vE
Q(hAV
interceptors"> ~?lmkfy
#W L>ha
v
<!-- The default interceptor stack name `~qVo4V6Z
1lv.@-
--> 8U-<Q>
<default-interceptor-ref 8{Wh4~|+
niCq`!
name="myDefaultWebStack"/> sQ82(N7l
# 9ZO1\
<action name="listUser" I9cZZ`vs
~0{F,R.$
class="com.adt.action.user.ListUser"> G4f%=Z
<param `]l[p+DO
{/qq*0wa
name="page.everyPage">10</param> 9q<?xO
<result ^0"[l {
/gLi(Uw
name="success">/user/user_list.jsp</result> Zu^J X/um
</action> EMS$?"K
ARid
</package> kc"SUiy/
_
3jY,*
</xwork> `vrLFPdO
% wh>_Ho
`S/;S<';
a#P{ [
ey[+"6Awne
d?OsVT;U
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 {(`xA,El
h&t9CpTfeJ
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 +dK;\wT
VQ`a-DL
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 nnnq6Z}
3C;nC?]K
JwmH_nJ(
4kf8Am(
\&X*-T[]j
我写的一个用于分页的类,用了泛型了,hoho E#+|.0*!s
!bIhw}^C*
java代码: ?{-y? %y
HY'-P&H5(
q*K.e5"'
package com.intokr.util; o[K,(
|1"n\4$
import java.util.List; h-RL`X
+#
tmsv]2
/** VH$hQPP5d
* 用于分页的类<br> ]s:%joj%^
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #vvQ1ub
* ;*8,PV0b_<
* @version 0.01 !qVnziE,,
* @author cheng 8 gzf$Oc
*/ p EbyQ[
public class Paginator<E> { S9S%7pE
privateint count = 0; // 总记录数 xy1R_*.F^T
privateint p = 1; // 页编号 y[sO0u\
privateint num = 20; // 每页的记录数 8Ir
= @
privateList<E> results = null; // 结果 [cf!%3>53
Ln5g"g8gb%
/** #x5?RHX56
* 结果总数 5KDN8pJN
*/ "\M^jO
publicint getCount(){ K)r|oW=6Y
return count; p v*n.U6
} $n@B:kv5p
L)j<;{J/Q0
publicvoid setCount(int count){ MFm2p?zPm
this.count = count; <ULydBom
} K-drN)o
+OC~y:
/** q`^T7
* 本结果所在的页码,从1开始 q <Zza
* k'JfXrW<!
* @return Returns the pageNo. =-|,v*
*/ O4fl$egQU
publicint getP(){ %.VFj7J
return p; T:(c/>
} 'Q F@@ 48
I9;,qd%<T
/** `E2HQA@
* if(p<=0) p=1 Z`Sbq{Kx
* L4-v'Z;
* @param p :LEC[</yvl
*/ As-xO~ +
publicvoid setP(int p){ C;NG#4;'
if(p <= 0) -7:_Dy
p = 1; (S1Co&SX
this.p = p; 1=Nh<FuQ
} ct![eWsuB
~zT7 43
/** R\d)kcy4
* 每页记录数量 sW]fPa(cn,
*/ ,c9K]>8m`
publicint getNum(){ =S:Snk%
return num; R;EdYbiF b
} zyi;vu
w_]`)$9
/** X(*MHBd
* if(num<1) num=1 .-HwT3
*/ 9S]]KEGn4
publicvoid setNum(int num){ H$={i$*,Y
if(num < 1) XdxSi"+
num = 1; >qC,IQ'
this.num = num; r`GA5}M
} 5isqBu
G"|`&r@
/** %$CV?K$C
* 获得总页数 cHjnuL0fsy
*/ qaZQ1<e
publicint getPageNum(){ p]erk
return(count - 1) / num + 1; ]
g]^^
} GjH$!P=.
Ny2. C?2
/** pW4$$2S?9
* 获得本页的开始编号,为 (p-1)*num+1 /U5!]7&gB
*/ RJk4 2;]
publicint getStart(){ nBJ'ak
return(p - 1) * num + 1; Uon^z?0A
} ?0J&U4
c$#7Kp4
/** 4(D/~OG-6
* @return Returns the results. rK} =<R
*/ 3P2x%G p
publicList<E> getResults(){ C
5
xsh
return results; d !=AS
} ?3=y]Vb+
tqXr6+!Q
public void setResults(List<E> results){ ^R7|x+
this.results = results; ^9fY%98
} %v)O!HC}
h 1REL^!c
public String toString(){ OH/!Ky\@
StringBuilder buff = new StringBuilder 6Mh"{N7
#Q'j^y7=z
(); V18A|]k
buff.append("{"); ^LAnR>mz^r
buff.append("count:").append(count); &Xh_`*]ox
buff.append(",p:").append(p); :^H2D=z@
buff.append(",nump:").append(num); vMYL( ]e
buff.append(",results:").append
5VZZk%oy
5DxNHEuS
(results); 1 3K|=6si
buff.append("}"); @P@{%I
return buff.toString(); A} v;uNS]
} )/cf%
u%sfHGrH
} hh7unHt-
(bp4ly^
|e{ ^Yf4