Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 tNskB`541
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 K#=)]qIk
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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+}6qfc$9k
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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 QES[/i +
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分页支持类: t}E1NXW
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java代码: /"t*gN=wrF
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package com.javaeye.common.util; Z=sC YLm
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import java.util.List; NXvu}&H
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publicclass PaginationSupport { $vS`w4Y
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publicfinalstaticint PAGESIZE = 30; OT_w<te
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privateint pageSize = PAGESIZE; tQy@d_a=y
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privateList items; Bv^{|w
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privateint totalCount; K8.=bGyg
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privateint[] indexes = newint[0]; =kq!e
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privateint startIndex = 0; ;r[@;2p*(
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public PaginationSupport(List items, int &~+lXNXF
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totalCount){ $/%|0tQ
setPageSize(PAGESIZE); jUq^$+N
setTotalCount(totalCount); /@5X0m
setItems(items); #c5 NFU}9
setStartIndex(0); C3af>L@}
} =GpO}t">
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public PaginationSupport(List items, int Kc= &jCn
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totalCount, int startIndex){ %C%~f{4
setPageSize(PAGESIZE); T`{W$4XS
setTotalCount(totalCount); uj$b/I>.'
setItems(items); f1;Pzr
setStartIndex(startIndex); ,z1X{
} {]~b^=qE$
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public PaginationSupport(List items, int j+:q:6 =
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totalCount, int pageSize, int startIndex){ +*3\C!
setPageSize(pageSize); BzL>,um
setTotalCount(totalCount); Qo{Ez^q@J
setItems(items); Oslbt8)U6
setStartIndex(startIndex); oB:tio4DE
} {~a=aOS
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publicList getItems(){ 7WG"_A~V
return items; ~A+DH
} m!s/L,iJJ
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publicvoid setItems(List items){ 6elmLDMni\
this.items = items; *5iNw_&
} B98&JoS
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publicint getPageSize(){ _f%Wk>A4
return pageSize; lH/d#MT
} ajuwP1I
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publicvoid setPageSize(int pageSize){ Z |uII#lq
this.pageSize = pageSize; 'G3B02*
} )/h~csy:~
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publicint getTotalCount(){ \D] N*
return totalCount; _NAKVzo-
} GMLq3_'
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publicvoid setTotalCount(int totalCount){ O0#wM-M
if(totalCount > 0){ ["}0umt
this.totalCount = totalCount; R=~+- ^O!
int count = totalCount / U]lXw+&
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pageSize; oJy ]n9
if(totalCount % pageSize > 0) [^B04x@
count++; _ 97
indexes = newint[count]; ~qm<~T_0
for(int i = 0; i < count; i++){ yzt6
indexes = pageSize * |D
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} K'~wlO@O
}else{ _>B0q|]j4'
this.totalCount = 0; =CEQYk-y1
} yzW9A=0A)
} ygr[5Tl
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publicint[] getIndexes(){ Z[
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return indexes; S+A'\{f
} QD%~A0
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publicvoid setIndexes(int[] indexes){ zlIXia5
this.indexes = indexes; dL'hC#!h
} VL"!.^'c
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publicint getStartIndex(){ NvWwj%6]
return startIndex; 306C_M\$
} CXGq>cQ=d
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publicvoid setStartIndex(int startIndex){ E~]8>U?V
if(totalCount <= 0) ^HumyDD6
this.startIndex = 0; P&C,E E$
elseif(startIndex >= totalCount) E^ _P
this.startIndex = indexes x]lv:m\)jT
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[indexes.length - 1]; S P)$K=
elseif(startIndex < 0) $:w4_X5T
this.startIndex = 0; S/& _
else{ 0f/=C9L
this.startIndex = indexes ,/{mRw%
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[startIndex / pageSize]; )s(J8J[b*L
} ,Khhu%$
} N7k<q=r-
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publicint getNextIndex(){ mV0F^5
int nextIndex = getStartIndex() + q05_5
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pageSize; 8
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if(nextIndex >= totalCount) n.p6+^ES
return getStartIndex(); AxLnF(eG
else 4;WeB
return nextIndex; {4Cn/}7Ly^
} "TA r\;[
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publicint getPreviousIndex(){ I{AteL
int previousIndex = getStartIndex() - \Rop~gD
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pageSize; Ha9A5Ao}0
if(previousIndex < 0) g
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return0;
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else 4(Gs$QkSo|
return previousIndex; " &'Jw
} 'F^nW_ryW
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} NJSzOL_
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抽象业务类 B5pMcw
java代码: h.FC:ym"
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/** )vO;=%GQ
* Created on 2005-7-12 cZT;VmC
*/ 1ux~dP
package com.javaeye.common.business; /\*,|y\<
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import java.io.Serializable; I^sWf3'db
import java.util.List; YG$2ySkDhE
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import org.hibernate.Criteria; 5*~Mv<#
import org.hibernate.HibernateException; EL$"MT}p
import org.hibernate.Session; |^Nz/PN
import org.hibernate.criterion.DetachedCriteria; p"f=[awp
import org.hibernate.criterion.Projections; -q\5)nY
import 4Waot
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org.springframework.orm.hibernate3.HibernateCallback; (-Rh%ZHH
import oomB/"Z
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org.springframework.orm.hibernate3.support.HibernateDaoS |&+g ,A _w
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upport; pe=Ou0
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import com.javaeye.common.util.PaginationSupport; &hWLG<IE
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public abstract class AbstractManager extends fBS`b[x
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HibernateDaoSupport { FLdO
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privateboolean cacheQueries = false; de]r9$D
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privateString queryCacheRegion; }c(".v#
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publicvoid setCacheQueries(boolean N8|=K_;&
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cacheQueries){ zq-"jpZG
this.cacheQueries = cacheQueries; {^gbS
} AEaT
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publicvoid setQueryCacheRegion(String n~N>c*p
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queryCacheRegion){ *f|9A/*B3
this.queryCacheRegion = T">-%-t
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queryCacheRegion; x
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} ?F' gh4
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publicvoid save(finalObject entity){ hWpn~q
getHibernateTemplate().save(entity); '(A)^K>+
} T0n=nC}<
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publicvoid persist(finalObject entity){ J&UFP{)
getHibernateTemplate().save(entity); |1J=wp)#
} *%_:[>
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publicvoid update(finalObject entity){ R<
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getHibernateTemplate().update(entity); e:}8|e~T
} Q#P=t83
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publicvoid delete(finalObject entity){ $~c?qU
getHibernateTemplate().delete(entity); 3?I^D /K^
} x'*,~u
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publicObject load(finalClass entity, \ &1)k/
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finalSerializable id){ vr56
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return getHibernateTemplate().load "8|y
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(entity, id); opTDW)
} OQ"%(w>Hb
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publicObject get(finalClass entity, b3}928!D-@
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finalSerializable id){ ?Z%Ja_}8ma
return getHibernateTemplate().get mMmzi4HL
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(entity, id); f%9EZ+OP
} 8>a/x ,
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publicList findAll(finalClass entity){ ?l#9ydi?
return getHibernateTemplate().find("from rm2"pfs
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" + entity.getName()); [Z6]$$!#2
} j-|YE?AA
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publicList findByNamedQuery(finalString L(Q v78F
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namedQuery){ |`T3H5X>
return getHibernateTemplate bep}|8,#u
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().findByNamedQuery(namedQuery); Ge$cV}
} ;AKtbS;H
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publicList findByNamedQuery(finalString query, G3&ES3L
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finalObject parameter){ !J!zi
return getHibernateTemplate pgz3d{]ua
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().findByNamedQuery(query, parameter); Va Z+TE
} =MO2M~e!
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publicList findByNamedQuery(finalString query, J411bIxD+q
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finalObject[] parameters){ +(3"XYh
return getHibernateTemplate ; iQ@wOL]
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().findByNamedQuery(query, parameters); Y9~;6fg
} k9UmTvX
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publicList find(finalString query){ %lNWaA
return getHibernateTemplate().find E
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(query); VA.jt}YGE
} GyJp!
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publicList find(finalString query, finalObject uHBX}WH
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parameter){ bT-(lIU
return getHibernateTemplate().find J]ivIQ
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(query, parameter); DrbjqQL+.
} =N01!?{
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public PaginationSupport findPageByCriteria #C|:]moe
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(final DetachedCriteria detachedCriteria){ 8
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return findPageByCriteria 6HpSZa
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); udB:ys
} nk9hQRP?
8
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public PaginationSupport findPageByCriteria a{Y:hrd:Z
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(final DetachedCriteria detachedCriteria, finalint @I}:HiF
?
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startIndex){ mU:C{<Z
return findPageByCriteria tp$NT.z
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(detachedCriteria, PaginationSupport.PAGESIZE, VA4vAF
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startIndex); =%Gecj
} n|NI]Qi*
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public PaginationSupport findPageByCriteria 1JgnuBX"
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(final DetachedCriteria detachedCriteria, finalint `ea;qWy
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pageSize, xXH%7%W'f
finalint startIndex){ Nt67Ye3;
return(PaginationSupport) e.G&hJr
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getHibernateTemplate().execute(new HibernateCallback(){ wM (!9Ws3
publicObject doInHibernate ^mFuZ~g;?
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(Session session)throws HibernateException { )vOZp&
Criteria criteria = ?yddr`?W
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detachedCriteria.getExecutableCriteria(session); oe`oUnN
int totalCount = T2Cdw\
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((Integer) criteria.setProjection(Projections.rowCount fMwJwMT8
8kAG EiC
()).uniqueResult()).intValue(); h3aHCr E
criteria.setProjection 9?gLi!rd
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(null); ?nrd$,
List items = ^C>i(j&
;E:ra_l
criteria.setFirstResult(startIndex).setMaxResults ?v#t{e0eQ
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(pageSize).list(); Rb<aCX
PaginationSupport ps = 3s\2 9gq
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new PaginationSupport(items, totalCount, pageSize, s!Y>\3rMW
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startIndex); 82Nh;5Tr
return ps; r$;DA<<|<c
} .qy._C2(
}, true); w |>:mQnU
} ?A(=%c|,g
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public List findAllByCriteria(final wGd8q xa
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DetachedCriteria detachedCriteria){ RoM'+1nP:#
return(List) getHibernateTemplate _.J{U0N
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().execute(new HibernateCallback(){ W6&".2
publicObject doInHibernate [:a;|t
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(Session session)throws HibernateException { Y1{6lhxgE
Criteria criteria = E8jdQS|i
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detachedCriteria.getExecutableCriteria(session); &k&tkE
return criteria.list(); nE]R0|4h
} $k@reN9
}, true); 9XF+?
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} :CSys62
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public int getCountByCriteria(final q ]rsp0P2
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DetachedCriteria detachedCriteria){ |GL#E"[&'
Integer count = (Integer) {\`#,[
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getHibernateTemplate().execute(new HibernateCallback(){ o?$D09j;;
publicObject doInHibernate A[XEbfDO
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(Session session)throws HibernateException { 2 'xT%
Criteria criteria = p4<&N MG
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detachedCriteria.getExecutableCriteria(session); |?V6__9
return T$GhE
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criteria.setProjection(Projections.rowCount 3?Bq((
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()).uniqueResult(); n1DD+@
} n0@e%=H)I
}, true); L\nWhmwl
return count.intValue(); t LS5yT/
} L2P~moVIi
} ED[PP2[/
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用户在web层构造查询条件detachedCriteria,和可选的 xlqRW"
u` `FD
startIndex,调用业务bean的相应findByCriteria方法,返回一个 "^zxq5u
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PaginationSupport的实例ps。 E$4\Yc)(AL
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ps.getItems()得到已分页好的结果集 e}(ws~.
ps.getIndexes()得到分页索引的数组 %1@+pf/
ps.getTotalCount()得到总结果数 GasIOPzK
ps.getStartIndex()当前分页索引 d;:+Xd`
ps.getNextIndex()下一页索引 6jRF[N8
ps.getPreviousIndex()上一页索引 xO'1|b^&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 u <%,Ql
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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 fJd!;ur)0
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一下代码重构了。 6@ET3v
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我把原本我的做法也提供出来供大家讨论吧: N#6&t8;kTC
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首先,为了实现分页查询,我封装了一个Page类: mj%Iow.
java代码: )e4nKh],
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/*Created on 2005-4-14*/ oslrv7EK
package org.flyware.util.page; K
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/** EbY%:jR
* @author Joa [|<|a3']|
* "DjD"?/b
*/ }PK8[N
publicclass Page { i0L)hkV
;I:jd")
/** imply if the page has previous page */ v /G,
privateboolean hasPrePage; 9H" u\t|?
x
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/** imply if the page has next page */ 06]J]
privateboolean hasNextPage; kRTT
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/** the number of every page */ x!tCK47Yq
privateint everyPage; [wjA8d.
L@ql)Lc);
/** the total page number */ H--(zxK
privateint totalPage; ,-vbR&
_Sosw|A
/** the number of current page */ P,j)m\|
privateint currentPage; [L{q
ql2>C.k3L
/** the begin index of the records by the current 2Af1-z^^K
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query */ ?r'rvu'/
privateint beginIndex; R}#?A%,*
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/** The default constructor */ wZ0$ylEX
public Page(){ #:v|/2
w=rh@S]
} =CFO]9
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/** construct the page by everyPage <omSK-
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* @param everyPage * A@~!@XE4
* */ /Pxt f~$
public Page(int everyPage){ *=$Jv1"Q
+
this.everyPage = everyPage; bsmZR(EnU
} Cz+`C9#
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/** The whole constructor */ N*f?A$u/I
public Page(boolean hasPrePage, boolean hasNextPage, {<v?Z_!68
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l <Tkg9
int everyPage, int totalPage, =d!3_IZ
int currentPage, int beginIndex){ -L NJ*?b
this.hasPrePage = hasPrePage; ?.LS_e_0
this.hasNextPage = hasNextPage; .Lr;{B
this.everyPage = everyPage; x<>#G~-
this.totalPage = totalPage; XPBKQm_}
this.currentPage = currentPage; ?R(fxx
this.beginIndex = beginIndex; yS0!#AG
} X"z^4?Aj+
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/** MD1n+FgTu
* @return L09YA
* Returns the beginIndex. K63OjR>H
*/ &u&/t?
publicint getBeginIndex(){ c/jU+,_g
return beginIndex; "iMuA
} %d c=QSL
+g(>]!swb
/** [d`J2^z}
* @param beginIndex @>}!g9c
* The beginIndex to set. CCNrjaA
*/ E].hoq7WiB
publicvoid setBeginIndex(int beginIndex){ Bk_23ygO_
this.beginIndex = beginIndex; j_H9l,V
} )>QpR8
G-
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/** <'>c`80@\*
* @return v,I4ozDx
* Returns the currentPage. ve49m%NQ
*/ bJ4} )P&
publicint getCurrentPage(){ *P7 H=Yf&
return currentPage; h64<F3}
} !i,Eo-[Z
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/** s!:'3[7+
* @param currentPage $Ypt
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* The currentPage to set. Hz) Xn\x
*/ V^;2u
publicvoid setCurrentPage(int currentPage){ }F!tM"X\
this.currentPage = currentPage; WWhAm{m
} fd!bs*\X
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/** vMu6u .e
* @return >x9@if
* Returns the everyPage. lD)ZMaaS3
*/ Hb55RilC
publicint getEveryPage(){ D_]4]&QYT
return everyPage; S~()A*5
} wXZ"}uT<}
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/** "m,)3zND3
* @param everyPage R&KFF'%
* The everyPage to set.
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*/ _JNSl2
publicvoid setEveryPage(int everyPage){ s;e%*4
this.everyPage = everyPage; #
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} )l g>'O
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/** 2n+tc
* @return GVR/p
* Returns the hasNextPage. 3V=wW{;x
*/ >!sxX = <
publicboolean getHasNextPage(){ bca4'`3\|
return hasNextPage; $$F iCMI
} e0;0 X7
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/** ~+|Vzm|S}
* @param hasNextPage 0h/bC)z
* The hasNextPage to set. =\~<##sRJ
*/ u#!QIQW
publicvoid setHasNextPage(boolean hasNextPage){ tf[)Q:|
this.hasNextPage = hasNextPage; a;bmZh
} ZDny=&>#
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/** %4' <0
* @return eFKF9m
* Returns the hasPrePage. ;$,b
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*/ n=Ze p{^
publicboolean getHasPrePage(){ JOwm|%>3a
return hasPrePage; =d`w~iC
} MTXh-9DA
,/2&HZd
/** 9`y@2/!Y
* @param hasPrePage M`V<`
* The hasPrePage to set. *I]/ [d
*/ +2xgMN6B@
publicvoid setHasPrePage(boolean hasPrePage){ 9Xl[AVs:M
this.hasPrePage = hasPrePage; sE^ee2]OI@
} B703{k
sU Er?TZ
/** &_cH9zw@
* @return Returns the totalPage. HOt,G
_{
* Gb!R>WY
*/ 8ShIn@|32
publicint getTotalPage(){ IC"Z.'Ph
return totalPage; ^+p7\D/E(
} MHj
RPh
6a}
/** GHNw.<`l?
* @param totalPage }fO+b5U
* The totalPage to set. gcF:/@:Rm
*/ Upw`|$1S
publicvoid setTotalPage(int totalPage){ 0\zY?UUww
this.totalPage = totalPage; )DB\du
} BTc
}Kfae
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} 9$k0
~ Y/:]&wF
OEw#;l4 C
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l
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 rjK]zD9
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个PageUtil,负责对Page对象进行构造: H2lQ(Y+H
java代码: ;
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/*Created on 2005-4-14*/ <*Nd%Ca
package org.flyware.util.page; R_^0Un([
+Jm~Um!
import org.apache.commons.logging.Log; N C%96gfD
import org.apache.commons.logging.LogFactory; 60TM!\
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/** }1
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* @author Joa ]sTb Ew.[
* s<>d&W 0=
*/ qCkC 2Fy(
publicclass PageUtil { v]Fw~Y7l!
"%}24t%
privatestaticfinal Log logger = LogFactory.getLog >{S
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A!cY!aQ
(PageUtil.class); :6MV@{;PJ
xv"v='
/** dBw7l}
* Use the origin page to create a new page |yl,7m/B-G
* @param page ''dS{nQs
* @param totalRecords Al1_\vx7
* @return n:|a;/{I]9
*/ {p.^E5&
publicstatic Page createPage(Page page, int &@K6;T
b)eoFc)lc
totalRecords){ 1etT."
return createPage(page.getEveryPage(), 9(3]t}J5
d
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page.getCurrentPage(), totalRecords); nll=Vd[
} GKc?
7KesfH?
/** u*f`\vs
* the basic page utils not including exception /WGD7\G'8
q68CU~i*
handler JC0# pU;
* @param everyPage yh2)Pc[
* @param currentPage <Drm#2x!E
* @param totalRecords 4a0Ud !Qcs
* @return page ~&?57Sw*m
*/ 2vTO>*t
publicstatic Page createPage(int everyPage, int 2?Y8hm
$l2`@ia"
currentPage, int totalRecords){ 9a[1s|>w-
everyPage = getEveryPage(everyPage); 0W0GSDx
currentPage = getCurrentPage(currentPage); 3!
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int beginIndex = getBeginIndex(everyPage, ;A4qE W
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currentPage); r?itd)WC<X
int totalPage = getTotalPage(everyPage, 7t+d+sQ-l
mPU}]1*p
totalRecords); Zs(BViTb|
boolean hasNextPage = hasNextPage(currentPage, SwsJ<Dq^z
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totalPage); 3?K+wg s
boolean hasPrePage = hasPrePage(currentPage); 6cd!;Ca
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returnnew Page(hasPrePage, hasNextPage, ?wu@+
everyPage, totalPage, @0]w!q
currentPage, 0C;Js\>3]
8 :WN@
beginIndex); w$IUm_~waa
} 4#{f8
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privatestaticint getEveryPage(int everyPage){ ^KdT,^6T
return everyPage == 0 ? 10 : everyPage; fF(AvMsO
} (/2rj[F&
t{>#)5Pqv
privatestaticint getCurrentPage(int currentPage){ \6 1H(,
return currentPage == 0 ? 1 : currentPage; )!kt9lK
} tA^+RO4
T$`m!mQ4
privatestaticint getBeginIndex(int everyPage, int S{?l/*Il*_
aGBd~y@e
currentPage){ 5kGQf
return(currentPage - 1) * everyPage; w[F})u]E
} 8nng^
=/}Rnl+c
privatestaticint getTotalPage(int everyPage, int !uit
/Yb8= eM
totalRecords){ ?%`Ph ?BZl
int totalPage = 0; -.r"|\1X
yUWc8]9\W
if(totalRecords % everyPage == 0) D_?Tj
totalPage = totalRecords / everyPage; ZR
-RzT1
else u(FOSmNkN
totalPage = totalRecords / everyPage + 1 ;
&a4FGzR#
#q K.AZi
return totalPage; J90:c@O"w
} Q>\Ho'
A1F$//a
privatestaticboolean hasPrePage(int currentPage){ Dt<MEpbur
return currentPage == 1 ? false : true; lX%-oRQ/os
} sVr|kvn2
KAXjvZN1
privatestaticboolean hasNextPage(int currentPage, t
#Kucde
KB^8Z@(+
int totalPage){ V,=5}qozQ
return currentPage == totalPage || totalPage == XlD=<$Nk7
!yT=*Cj4
0 ? false : true; qtdkK LT
} )^BZ,e
f,i2U|1pbj
K\KQ(N8F
} y{&%]Fq
<5
k-a1^K3
A9N8Hav
oexTz[
hxj\
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。 &"WgO!pzD
>]anTF`d
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 Bd]rak'
w>\oz
做法如下: j94~cYV
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 O'B3s y
+,,dsL
的信息,和一个结果集List: .wp[uLE
java代码: cLp_\\
5=8v\q?)c
t\LE\[XM>
/*Created on 2005-6-13*/ 50dN~(;p
package com.adt.bo; )b (+=
\BH?GMoP
import java.util.List; W!T[
^+
s-5#P,Lw
import org.flyware.util.page.Page; 7FkiT
VRgckh
m
/** n|? sNM<J3
* @author Joa OM^`P
*/ =$+0p3[r
publicclass Result { ?]bx]Y;
ZbVn"he
private Page page; )X," NJG
"=K3sk
private List content; V~#5^PF{
I$S*elveG
/** jl}!UG
* The default constructor Xs|d#WbX
*/ *;Mc X
public Result(){ 9{U@s
super(); *g
%bdO
} M@7U]X$g
[kpQ:'P3
/** $L( ,lB
* The constructor using fields mE1Vr
* =SuJ*
* @param page /eU\B^k
* @param content KPDJ$,:
*/ V1Ojr~iM
public Result(Page page, List content){ w8~R=k
this.page = page; (=WbLNBS
this.content = content; olr#3te
} N.+A-[7,W
~3Pp}eO~V
/** <,it<$f#
* @return Returns the content. >Ik%_:CC`
*/ _-H,S)kI`
publicList getContent(){ Vt \g9-[
return content; =jh^mD&'
} TD*AFR3Oz
^tSwA anP\
/** h?;03>6A&]
* @return Returns the page. A@?-"=h}
*/ ns~bz-n
public Page getPage(){ r QNm2h
return page; +~YoP>
} 2Mq@5n
_t;^\"\
/** -IVWkA)7
* @param content OGLA1}k4
* The content to set. {S-M] LE
*/ J E5qR2VA
public void setContent(List content){ Z_dL@\#|
this.content = content; K:qc
"Q=C
} vol (%wB
},}g](!m
/** t~dK\>L
* @param page x!W5'DO
* The page to set. /&G|.Cx
*/ ltU{P|7!E
publicvoid setPage(Page page){ P.Cn[64a+@
this.page = page; Y1>OhHuN
} p ^TCr<=
} >dgq2ok!u
zsd<0^
p\{
7&HcrkP]
v5e*R8/
TG8 U=9qt
2. 编写业务逻辑接口,并实现它(UserManager, vfj{j=
G
<h+@;/v:
UserManagerImpl) jA2%kX\6//
java代码: tI^[|@,
pRxVsOb
FIAmAZH}_
/*Created on 2005-7-15*/ %jf|efxo
package com.adt.service; 7rbw_m`12-
'byTM?Sp{
import net.sf.hibernate.HibernateException; (RrC<5"
o(> #}[N}
import org.flyware.util.page.Page; Z
eY*5m
3LJ\y
import com.adt.bo.Result; ?G7*^y&Q
@c"s6h&
/** c;(Fz^&_
* @author Joa 5kWzD'!^
*/ M&q~e@P
publicinterface UserManager { @p/"]zf
P.k>6T<U>
public Result listUser(Page page)throws 4bdCbI
t>LSP$
HibernateException; ~#VDJ[Z
9vW]HOK
} Y`$\o
50A\Y)i_mZ
0wSy[z4V
f-H"|9
b KIL@AI
java代码: %qE"A6j
FL^t}vA
VK,{Mu=.9
/*Created on 2005-7-15*/ {[/A?AV;F
package com.adt.service.impl; ?dv-`)S&
~Al3Dv9x
import java.util.List; .q:6F*,1M
ZdY$NpR,
import net.sf.hibernate.HibernateException; Btr>ek
cBOK@\x:Wi
import org.flyware.util.page.Page; c05-1
import org.flyware.util.page.PageUtil; _*{Lha
`D=d!!1eUi
import com.adt.bo.Result; 2u5\tp?8
import com.adt.dao.UserDAO; L:?Ew9Lf
import com.adt.exception.ObjectNotFoundException; /[/{m ]
import com.adt.service.UserManager; $\1M"a}F
lx2%=5+i;
/** -bSM]86
* @author Joa Pf?&ys6
*/ CK|AXz+EN
publicclass UserManagerImpl implements UserManager { VG$;ri>
z%JN| 5
private UserDAO userDAO; y] O&w{m$
Fo%`X[ ?
/** #4"eQ*.*"
* @param userDAO The userDAO to set. Sd.Km a
*/ (~5]1S}F
publicvoid setUserDAO(UserDAO userDAO){ /F|VYl^_
this.userDAO = userDAO; Slv:CM
M
} `)KGajB
ea`6J
/* (non-Javadoc) ,z`D}<3
* @see com.adt.service.UserManager#listUser m]Qs
BK
%BMlcm7Ec
(org.flyware.util.page.Page) :f_oN3F p
*/ #uC}IX2n
public Result listUser(Page page)throws FzCXA=m
P\{s C6E
HibernateException, ObjectNotFoundException { ^'Rs`e
int totalRecords = userDAO.getUserCount(); 9jx>&MnWs
if(totalRecords == 0) GiK,+M"d
throw new ObjectNotFoundException q|s:&&Wf
` l'QAIo
("userNotExist"); *A}td8(
page = PageUtil.createPage(page, totalRecords); U,fPG/9
List users = userDAO.getUserByPage(page); vo)W
ziHh
returnnew Result(page, users); (Nd)$Oq[4
} K)[\IJJM
kVt/Hhd9
} <HS{A$]
JX&%5sn(
v^p* l0r6:
*u,xBC2C
k,<7)-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]-a/)8
G-]<+-Q$4
询,接下来编写UserDAO的代码: OR'e!{
3. UserDAO 和 UserDAOImpl: "WXUz
java代码: 3i4m!g5Z?
>f-RzQ k
ER[$TH&
/*Created on 2005-7-15*/ z^4+Un
package com.adt.dao; 5
I#-h<SG
DR]oK_
import java.util.List; d$E>bo-\
0a@tPskV
import org.flyware.util.page.Page;
z.2UZ%:
rxJl;!7G
import net.sf.hibernate.HibernateException; S+mBVk"-~S
I1dOMu9
/** Q[H4l({E
* @author Joa s,/C^E
*/ ;<+Z}d/g9
publicinterface UserDAO extends BaseDAO { 4 R8Qn^
Ic&YiATj
publicList getUserByName(String name)throws IeA/<'Us
Ro<5c_k
HibernateException; L>hLYIW
3KkJQ5a
publicint getUserCount()throws HibernateException; R `ob;>[Q
/S^>06{-+
publicList getUserByPage(Page page)throws ^HTvw~]5
|m*l/@1
HibernateException; >lek@euqw
jG}nOI
} f8f3[O!x
yw7bIcs|#b
meThjCC
GN5*
%=s2>vv9
java代码: [x`),3qD
2pSp(@N3
Wap\J7NY
/*Created on 2005-7-15*/ ]ERAt^$0
package com.adt.dao.impl; K9nW"0>
!Zc#E,
import java.util.List; B7[#z{8'#
A%&lW9z7
import org.flyware.util.page.Page; ~rXLb:
0Am\02R.C,
import net.sf.hibernate.HibernateException; B_8JwMJu3
import net.sf.hibernate.Query;
y0) mBCX
[L| vBr
import com.adt.dao.UserDAO; ]1h9:PF
|A0U3$S=
/** ajkpU.6E:
* @author Joa d5{RIM|
*/ DM\pi9<m
public class UserDAOImpl extends BaseDAOHibernateImpl ggfCfn
c3<H272\
implements UserDAO { <@4V G
).Iifu|ks
/* (non-Javadoc) %Br1b6 V
* @see com.adt.dao.UserDAO#getUserByName {`>pigo
/%{CJ0Y
(java.lang.String) 0dD.xuor
*/ hX-^h2eV
publicList getUserByName(String name)throws rCA0c8
ICG:4n(,
HibernateException { W~l.feW$i
String querySentence = "FROM user in class *kj+6`:CPs
ox";%|PP1
com.adt.po.User WHERE user.name=:name"; $0~1;@`rQ6
Query query = getSession().createQuery LJ z6)kz
1NrNTBI@
(querySentence); rV-Xsf7Z
query.setParameter("name", name); /P/0\3TCi
return query.list(); o##!S6:A
} E=,fdyj.
P/k#([:2
/* (non-Javadoc) G \$x.
* @see com.adt.dao.UserDAO#getUserCount() =4!m]*y
*/ ^0I"
publicint getUserCount()throws HibernateException { fX1Ib$v
int count = 0; `:0Auw9h
String querySentence = "SELECT count(*) FROM C8(0|XX
"0z4mQ}>N
user in class com.adt.po.User"; XN3'k[
Query query = getSession().createQuery <0Gk:NB,
- xyY6bxL
(querySentence); ybIqn0&[
count = ((Integer)query.iterate().next iUqD>OV
Fd%JF#Hk
()).intValue(); T=g2gmo9
return count; PbV1FB_
} 4O{,oN~7
D7jbo[GgS
/* (non-Javadoc) #B_H/9f(
* @see com.adt.dao.UserDAO#getUserByPage H5jk#^FD
Tg=P*HY6
(org.flyware.util.page.Page) Tx'anP
*/ 4:s,e<Tc4v
publicList getUserByPage(Page page)throws &C?4'e
br?pfs$U
HibernateException { f&Juq8s_0
String querySentence = "FROM user in class lXVh`+X/l
/(%!txSNEt
com.adt.po.User"; CRNt5T>qH
Query query = getSession().createQuery C_h$$G{S(
6y{CM/DC
(querySentence); TeJ=QpGW2
query.setFirstResult(page.getBeginIndex()) ArT@BqWd
.setMaxResults(page.getEveryPage()); .rl Lt5b%
return query.list(); $B]_^
} D|vck1C5,
.[?2_e#9 %
} I &%
Z*H
^i@0P}K<
eK\i={va
uj)fah?Wg
:{KpnJvd
至此,一个完整的分页程序完成。前台的只需要调用 L /N%ft]!T
?MSV3uODb
userManager.listUser(page)即可得到一个Page对象和结果集对象 sP>-k7K.
v*OT[l7
的综合体,而传入的参数page对象则可以由前台传入,如果用 ?ihRt+eR~
M~.1:%khM
webwork,甚至可以直接在配置文件中指定。 W*u$e8i7
m,rkKhXP
下面给出一个webwork调用示例: 'W&ewZH_h
java代码: \23m*3"W
F84<='K
tU.~7f#+A
/*Created on 2005-6-17*/ {]4Zpev
package com.adt.action.user; OgzKX>N`A
gA] 3h8%w
import java.util.List; *(Z\"o!
GgtYO4,
import org.apache.commons.logging.Log; Vf$$e)
import org.apache.commons.logging.LogFactory; E>u U6#v
import org.flyware.util.page.Page; VMu?mqEa
m mH
xPd
import com.adt.bo.Result; +Ur75YPh
import com.adt.service.UserService; X#fjIrn
import com.opensymphony.xwork.Action; ]na$n[T/I
nIfp0U*
/** |[)pQGw
* @author Joa !-JvVdM;(
*/ M'pIAm1p
publicclass ListUser implementsAction{ j.\0p-,
E!=Iz5
privatestaticfinal Log logger = LogFactory.getLog ]i>,oxBWe
c1
j@*6B
(ListUser.class); ;B{oGy.
`~NjBtQ
private UserService userService; JOwu_%
Ieh<|O,-C
private Page page; @=BApuer+
nL]eGC
privateList users; >Udq{<]#r
nZEew.T:6
/* ({cWb:+r
* (non-Javadoc) V \/Qik{h
* 7ab'q&Y[
* @see com.opensymphony.xwork.Action#execute() AN)r(86L
*/ Fv:x>qZr@
publicString execute()throwsException{ \:2z!\iP`
Result result = userService.listUser(page); 6!([Hu#= *
page = result.getPage(); *Xh#W7,<
users = result.getContent(); ?[)V
return SUCCESS; dt/-0~U
} t~":'le`zr
0#~k)>(7lR
/** Yaz/L)Y;R
* @return Returns the page. 7vc4 JO]
*/ Qm_;o(
public Page getPage(){ \~l"
return page; CV2#G *
} z|zEsDh;
J'yCVb)V
/** ScmwHid:\
* @return Returns the users. ,R=$qi|
*/ PzustC|
publicList getUsers(){ {Q@?CT
return users; q(Ow:3&
} .kJu17!
+Eel|)Z*Q
/** >:BgatyPH
* @param page n'%cO]nSx
* The page to set. at1oxmy
*/ *e:2iM)8~
publicvoid setPage(Page page){ 6P)D M
this.page = page; N,:G5WxW
} c{ qTVi5e
b`f6(6
/** TP)o0U
* @param users uO1^nK
* The users to set. v9(N}hoP
*/ Nnoj6+b
publicvoid setUsers(List users){ yV31OBC:
this.users = users; ezri9\Ju
} qOa*JA`
uA cvUN-@
/** ;alt% :$n
* @param userService 'R99m?"
* The userService to set. %Z8pPH~T
*/ <vu~EY0.
publicvoid setUserService(UserService userService){ %4BQY>O)@
this.userService = userService; u#Bj#y!
} D&]xKx
} $-<yX<.
/AYq^
k?/! `
$>Ow<!c
1f?Fuw
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, kV3LFPf>0
;Rm';IW$
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 p:ZQ*Ue
O"_QDl<ya
么只需要: a
FWTm,)
java代码: z`D|O|#q
$}EARW9
0
t/mLw&
<?xml version="1.0"?> 8v)HTD/C
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork PTTUI
j
J54<.D
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ?q0a^c?A^
rxZk!- t)L
1.0.dtd"> }"q#"s
TT){15T;"
<xwork> _ -,[U{
[~;wCW,1
<package name="user" extends="webwork- pTJ_DH
'%YTMN@
interceptors"> Upm#:i|"
HD,6
<!-- The default interceptor stack name )a+bH </'
CM`Q((
--> UY:Be8C A
<default-interceptor-ref U<'$ \P
jASK!3pY
name="myDefaultWebStack"/> DvA#zX[
AAF;M}le,
<action name="listUser" t=[/L]!
Q1H.2JXr
class="com.adt.action.user.ListUser"> GW]t~EL
<param JBISA _Y
ADMeOdgca
name="page.everyPage">10</param> 'n?"f |G
<result dE(d'*+a
!'>#!S~h3
name="success">/user/user_list.jsp</result> U:$`M,762Z
</action> l8lJ &
T8j<\0WW
</package> #O'g*]j
#EH\Q%
</xwork> T$V8n_;
0BOL0<Wq
2[KHmdgtB
\ow(4O#
/]nrxT
7 S%`]M4;
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 `Cu9y+t
pU u')y
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。 MOIVt) ZY
\,`iu=YZv
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 >EgMtZ88.<
n|PW^kOE/
4 @9cO)m
#|Je%t}~
FWS!b!#,N
我写的一个用于分页的类,用了泛型了,hoho "fSK7%BP
Ge76/T%{Q
java代码: HA0yX?f]
n$"BF\eM
o* QZf*M
package com.intokr.util; 1rh2!4)7
@9MrTP
import java.util.List; "3?:,$*
*(VwD)*
/** ?gXdi<2Qn
* 用于分页的类<br> "%=K_WJ?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> <|:$_&(
* BagV\\#v4
* @version 0.01 ab<7jfFIa
* @author cheng NbUibxJ
*/ 'W[Nr
public class Paginator<E> { ]T>YYz
privateint count = 0; // 总记录数 QFEc?sEe
privateint p = 1; // 页编号 SxM5'KQ
privateint num = 20; // 每页的记录数 PMiG:bM
privateList<E> results = null; // 结果 o(xt%'L`t
)/t=g
/** QST-!`]v
* 结果总数 HOVzpj
*/ DZ5h<1
publicint getCount(){ ^^gV@fz
return count; diF2:80o
} QWK\6
jiLt *>I
publicvoid setCount(int count){ TK%MVL TK
this.count = count; Z`@< O%
} "ODs.m oq
Eb\SK"8
/** w Yr M2X@
* 本结果所在的页码,从1开始 ~ponYc.Y
* %>:d5"&Lbs
* @return Returns the pageNo. Z`'&yG;U
*/ u[coWaPsZ
publicint getP(){ }Ym~[S*x
return p; QdP)-Fx
} K]Q1VfeL=
$:0?"?o);
/** +?bOGUik
* if(p<=0) p=1 dn=g!=
* ILXV yU
* @param p 3 e<sNU?
*/ :8Jn?E (36
publicvoid setP(int p){ KEvT."t
if(p <= 0) %%k`+nK~
p = 1; HVcd< :g0
this.p = p; n4Eqm33
} KN zm)O
$ ~2qEe.h
/** Nn|~:9#
* 每页记录数量 {!7 ^w
*/ -<WQ>mrB&
publicint getNum(){ %$I@7Es>
return num; TZ%u;tBH:
} *ZA.O
3_+$x4%
/** 3 ~^ }R
* if(num<1) num=1 xk8P4`;d$
*/ xQ7-4N,
publicvoid setNum(int num){ O U3KB
if(num < 1) dD0:K3@
num = 1; 2kU=9W6ND
this.num = num; 3xGk@ 333
} Wo+'j $k
:If1zB)
/** geRD2`3;
* 获得总页数 d*xKq"+
&E
*/ s'|^ 6/
publicint getPageNum(){ rwUKg[
1N
return(count - 1) / num + 1;
Q>}*l|Ci
} Z6I^HG{:
L5tSS=
/** O7z-4r
* 获得本页的开始编号,为 (p-1)*num+1 %XieKL
*/ >>C(y?g
publicint getStart(){ OJ:iQ
return(p - 1) * num + 1; [LJ1wBMw
} 3G7Qo
Vg)]F+E
/** ,!?&LdPt>
* @return Returns the results. w1+xlM,,9
*/ O67.DEu^
publicList<E> getResults(){ '8 ~E
return results; Wl:vO^
} ?=;dNS@i@
|-c)OS3#D
public void setResults(List<E> results){ 420cJ{;A
this.results = results; tNI~<#+lg
} _f8<t=R
Nn],sEs
public String toString(){ %usy`4
2
StringBuilder buff = new StringBuilder ?6gC;B
[D=3:B&f
(); =*aun&
buff.append("{"); b[3K:ot+
buff.append("count:").append(count); /pvR-Id|6
buff.append(",p:").append(p); h<50jnH!
buff.append(",nump:").append(num); ^y,%Tv>
buff.append(",results:").append 4{d!}R
vt" 7[!O
(results); 4|*H0}HOm
buff.append("}"); _[8BAm
return buff.toString(); '1[}PmhD
} fCL5Et
VQ/<MY C
} > !thxG/_
VemgG)\
C~.7m-YW