Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1r3}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 *dsI>4%m
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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 SUjo%3R
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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 4AKPS&k;
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分页支持类: + 7wMM#z
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java代码: Q2*
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package com.javaeye.common.util; Sar1NkD#
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import java.util.List; 4`")aM
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publicclass PaginationSupport { GH`y-Ul'K
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publicfinalstaticint PAGESIZE = 30; ?MS!t6
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privateint pageSize = PAGESIZE; `O0y8
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privateList items; @7{.err!
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privateint totalCount; ^|2m&2
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privateint[] indexes = newint[0]; PM'2zP[*W
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privateint startIndex = 0; >=.3Vydi1
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public PaginationSupport(List items, int 1X9J[5|ll
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totalCount){ [\&2&
setPageSize(PAGESIZE); nwIj?(8x
setTotalCount(totalCount); {.J<^V
setItems(items); 3jHg9M23[^
setStartIndex(0); Sf@xP.d
} q4,/RZhzh
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public PaginationSupport(List items, int OU!."r`9
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totalCount, int startIndex){ G#A6<e/
setPageSize(PAGESIZE); 3{wuifS
setTotalCount(totalCount); MZ~N}y
setItems(items); _'*(-K5&
setStartIndex(startIndex); r`<x@,
} 8q;
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public PaginationSupport(List items, int ?TI]0)
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totalCount, int pageSize, int startIndex){ {CNJlr@z
setPageSize(pageSize); '%o^#gJ p
setTotalCount(totalCount); [8%q@6[
setItems(items); ,Z}ST|$u
setStartIndex(startIndex); @Bn4ZFB@
} m;L3c(r.
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publicList getItems(){ )g}G{9M^
return items; 6~x a^3G:
} tD4-Llj6
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publicvoid setItems(List items){ @.`k2lxGd~
this.items = items;
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} m_,Jbf
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publicint getPageSize(){ XL'\$f
return pageSize; yB 'C9wEH
} +wQ}ZP&
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publicvoid setPageSize(int pageSize){ M0OIcMTv
this.pageSize = pageSize; k4E9=y?
} B+Ft
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publicint getTotalCount(){ $`lm]} {&
return totalCount; \,r*-jr
} ]Tg@wMgI
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publicvoid setTotalCount(int totalCount){ ,t:P
if(totalCount > 0){ %~,Fe7#p
this.totalCount = totalCount; R.vOYzo
int count = totalCount / yO,Jgn
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pageSize; Wh~,?}laj
if(totalCount % pageSize > 0) 5)5yH bS
count++; 8si{|*;hL
indexes = newint[count]; -Q&@P3x
for(int i = 0; i < count; i++){ S4-jF D)U
indexes = pageSize * t)rPXvx}!
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} ZX8@/8sv
}else{ 7AWq3i{
this.totalCount = 0; A}&YK,$5ED
} .rnT'""i<5
} rBy0hGx
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publicint[] getIndexes(){ c;06>1=wP5
return indexes; OK YbEn#
} t1yOAbI
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publicvoid setIndexes(int[] indexes){ E'5KJn;_7
this.indexes = indexes; S\Le;,5Z
} l-S0Gn/'X
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publicint getStartIndex(){ o>bi~(H
return startIndex; q/d?cLgl
} yPs6_Qo!p
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publicvoid setStartIndex(int startIndex){ 5SmJ'zFO
if(totalCount <= 0) }maD8,:t
this.startIndex = 0; iHK.hs;
elseif(startIndex >= totalCount) P#`M8k
this.startIndex = indexes }pnp._j
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[indexes.length - 1]; -;FAS3(wy
elseif(startIndex < 0) <5P*uZ
this.startIndex = 0; 5h0Hk<N
else{ 5X>~39(r
this.startIndex = indexes Ei\>gXTH1-
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[startIndex / pageSize]; c_?^:xs:d
} @+Sr~:K
} UUb0[oy
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publicint getNextIndex(){ (@qS
int nextIndex = getStartIndex() + AE~@F4MK
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pageSize; 9!Jt}n?!g
if(nextIndex >= totalCount) dNF_T?E\
return getStartIndex(); `'k2gq&
else
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return nextIndex; * fj`+J
} uOy/c 8`
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publicint getPreviousIndex(){ $xq04ejJ
int previousIndex = getStartIndex() - OLm@-I*
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pageSize; yWE\)]9
if(previousIndex < 0) D
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return0; /!A"[Tyt
else 4[MTEBx
return previousIndex; kv, !"<
} D6+3f#k6
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} CR%h$+dzy
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抽象业务类 WBkx!{\z
java代码: r]DU
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/**
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* Created on 2005-7-12 -1d*zySL
*/ o?t H[
package com.javaeye.common.business; )b>misb/
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import java.io.Serializable; V45adDiZ
import java.util.List; /x$JY\cq`
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import org.hibernate.Criteria; fjl9*
import org.hibernate.HibernateException; LL)t)
import org.hibernate.Session; ^blw\;LB
import org.hibernate.criterion.DetachedCriteria; DI2e%`$
import org.hibernate.criterion.Projections; ls!A'@J
import !Ko>
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org.springframework.orm.hibernate3.HibernateCallback; VwZ~ntk
import ;in-)`UC!
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org.springframework.orm.hibernate3.support.HibernateDaoS ^_DwuY
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upport; ~> lqEa
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import com.javaeye.common.util.PaginationSupport; Ak('4j!*}^
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public abstract class AbstractManager extends {=mGXd`x?l
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HibernateDaoSupport { s@7h oU-+
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privateboolean cacheQueries = false; 4;CI<&S
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privateString queryCacheRegion; 3W_7xLA
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publicvoid setCacheQueries(boolean uL1lB@G@
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cacheQueries){ l"nS+z
this.cacheQueries = cacheQueries; 3o?eUwI}
} 'VCuMCV
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publicvoid setQueryCacheRegion(String 1Q? RD%lkf
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queryCacheRegion){ X#JUorGp
this.queryCacheRegion = oQu>Qr{Zp
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queryCacheRegion; K/f-9hE F
} 5|K[WvG@Co
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publicvoid save(finalObject entity){ 3Wv^{|^
getHibernateTemplate().save(entity); n5.sx|bI?
} xsJXf @
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); ./Ek+p*96H
} 6o3#<ap<
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publicvoid update(finalObject entity){ B>!mD{N
getHibernateTemplate().update(entity); JW^ ${4
} 7g+T
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publicvoid delete(finalObject entity){ DgW@v[#BK=
getHibernateTemplate().delete(entity); T@IzfX7
} F!)[H["_
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publicObject load(finalClass entity, Y)pop:y t
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finalSerializable id){ )lS04|s
return getHibernateTemplate().load `NgQ>KV!
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(entity, id); 37a1O>A
} 7I"~a<f0X`
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publicObject get(finalClass entity, rM
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finalSerializable id){ ~//E'V-
return getHibernateTemplate().get
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(entity, id); 9cP{u$
} Q*ELMib
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publicList findAll(finalClass entity){ ,
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return getHibernateTemplate().find("from s=jYQ5nv
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" + entity.getName()); vCJa%}
} ny1O- `!1
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publicList findByNamedQuery(finalString a@W9\b@I
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namedQuery){ 0q-lyVZ^X
return getHibernateTemplate ut560,h~
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().findByNamedQuery(namedQuery); }kvix{
} $[fq Th
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publicList findByNamedQuery(finalString query, Nr2,m"R{
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finalObject parameter){ (P-^ PNz&
return getHibernateTemplate PLs`Ci|`
tR'RB@kJ
().findByNamedQuery(query, parameter); M`'DD-Q
} 8Z9>h:c1
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publicList findByNamedQuery(finalString query, f7Nmvla[q
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finalObject[] parameters){ `j)56bR
return getHibernateTemplate W5`p Qdk
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().findByNamedQuery(query, parameters); l_:P|
} Nr>UZlU8
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publicList find(finalString query){ jwE=
return getHibernateTemplate().find <Y}m/-sD5
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(query); !PEKMDh
} FauASu,A
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publicList find(finalString query, finalObject h>GbJ/^
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parameter){ ~<VxtcEBz
return getHibernateTemplate().find i]k)wr(
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(query, parameter); eQ/w
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} #n|5ng|CJ
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public PaginationSupport findPageByCriteria =&UE67eK,
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(final DetachedCriteria detachedCriteria){ ^" ?a)KC
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); `&q+ f+z
} {u1|`=;
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public PaginationSupport findPageByCriteria 2ak]&ll+h
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(final DetachedCriteria detachedCriteria, finalint TU~y;:OJ
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startIndex){ `Pj7:[."[
return findPageByCriteria er3~gm
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(detachedCriteria, PaginationSupport.PAGESIZE, A9BoH[is7
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startIndex); dyn)KDS
} ~%>i lWaHB
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public PaginationSupport findPageByCriteria dNt^lx
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, }9\6!GY0
finalint startIndex){ 61kSCu
return(PaginationSupport) BI)C\D3[
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getHibernateTemplate().execute(new HibernateCallback(){ #bt f|\D
publicObject doInHibernate 9;7"S.7AV
@B>D>B
(Session session)throws HibernateException { 7_s+7x =
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); J{\U w].|0
int totalCount = q6-o!>dLQ
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((Integer) criteria.setProjection(Projections.rowCount +0%r@hTv&>
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()).uniqueResult()).intValue(); )JTQZ,f3]
criteria.setProjection ZJ2
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(null); oA-,>:}g{
List items = R~a9}&
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criteria.setFirstResult(startIndex).setMaxResults (y!bvp[" m
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(pageSize).list(); v^o`+~i
PaginationSupport ps = D^%IFwU^
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new PaginationSupport(items, totalCount, pageSize, P<&bAsje
FNLS=4
startIndex); `O2P&!9&
return ps; yD& Y`f#
} N(4y}-w$
}, true); }gXhN"
} JGvhw,g
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public List findAllByCriteria(final BSHS)_xs
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DetachedCriteria detachedCriteria){ HJg&fkHn1
return(List) getHibernateTemplate |^5"-3Q
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().execute(new HibernateCallback(){ C=&n1/
publicObject doInHibernate NYHK>u/5c
PA
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(Session session)throws HibernateException { g4,ldr"D
Criteria criteria = 8=Oym~
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detachedCriteria.getExecutableCriteria(session); n5"oXpcIx
return criteria.list(); J7",fb
} Yu" Q
}, true); oCkG
} ].J;8}
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public int getCountByCriteria(final ZlC+DXg#S
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DetachedCriteria detachedCriteria){ "TaLvworb4
Integer count = (Integer) *8,W$pe3
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getHibernateTemplate().execute(new HibernateCallback(){ 9kWI2cLzQt
publicObject doInHibernate )N- '~<N
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(Session session)throws HibernateException { !?ZR_=Y%
Criteria criteria = ?+d{Rh)y
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detachedCriteria.getExecutableCriteria(session); 8k:^( kByF
return !$1qnsz
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criteria.setProjection(Projections.rowCount baG_7>Q9H
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()).uniqueResult(); U'F}k0h?\'
} Ek `bPQ5
}, true); .GJbrz
return count.intValue(); ly34aD/p~,
} q
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} lbt8S.fx
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用户在web层构造查询条件detachedCriteria,和可选的 tik*[1it
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 \PT!mbB?
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PaginationSupport的实例ps。 .?3roQ
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ps.getItems()得到已分页好的结果集 M x,5
ps.getIndexes()得到分页索引的数组 _I; hM
ps.getTotalCount()得到总结果数 \,/ozfJ7dT
ps.getStartIndex()当前分页索引 rG~W=!bj
ps.getNextIndex()下一页索引 B=]L%~xL$
ps.getPreviousIndex()上一页索引 /2T
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,2Ed^!`
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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 FLQke"6i0:
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一下代码重构了。 'q;MhnU+
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我把原本我的做法也提供出来供大家讨论吧: ]7k:3"wH
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首先,为了实现分页查询,我封装了一个Page类: t1iz5%`p}
java代码: uZ_?x~V/
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/*Created on 2005-4-14*/ <!G /&T
package org.flyware.util.page; sdCG}..`
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/** fFbJE]jW
* @author Joa P]}:E+E<.I
* 11QZ- ^
*/ j^b&Q
publicclass Page { L T`T~|pz
YY tVp_)
/** imply if the page has previous page */ Y'P^]Q=}_#
privateboolean hasPrePage; k~<Ozx^AyY
e^\(bp+83
/** imply if the page has next page */ +|S)Mm8-
privateboolean hasNextPage; BR@gJ(2
LC=M{\
/** the number of every page */ 7\$}|b[9
privateint everyPage; ,ynN801\m
lgVT~v{U`n
/** the total page number */ T7ShE-X
privateint totalPage; In%FOPO
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/** the number of current page */ #+6j-^<_6
privateint currentPage; 7Tr '<(A
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/** the begin index of the records by the current Vo{
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query */ 0[
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privateint beginIndex; ]S?G]/k}
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/** The default constructor */ W=S^t_F
public Page(){ 1=+S'_j
*dB3Gu{
+
} D?Ol)aj?
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/** construct the page by everyPage @fo(#i&
* @param everyPage `3[W~Cq
* */ py~[M'p(H
public Page(int everyPage){ {be|G^.c
this.everyPage = everyPage; A`vRUl,c=
} TGG=9a]m
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/** The whole constructor */ A9Ea}v9:
public Page(boolean hasPrePage, boolean hasNextPage, 7w5l[a/
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+ rN#
int everyPage, int totalPage, yP-$@Ry
int currentPage, int beginIndex){ .aWwJZ=[
this.hasPrePage = hasPrePage; &u"mFweS
this.hasNextPage = hasNextPage; $@{d\@U
this.everyPage = everyPage; 90JWU$K
this.totalPage = totalPage; fRk'\jzT
this.currentPage = currentPage; %T<c8w}dP
this.beginIndex = beginIndex; ~9!@BL\
} 9@M;\ @&g
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/** +('xzW
* @return Xsb.xxK.
* Returns the beginIndex. (Y&gse1}!
*/ 56C'<#
publicint getBeginIndex(){ _8`S&[E?
return beginIndex; &kWT<*;J)
} M9VAs~&S
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/** .gRb'
* @param beginIndex h>xB"E|.
* The beginIndex to set. z:O:g?A
*/ g:c?%J
publicvoid setBeginIndex(int beginIndex){ 9ygNJX'~
this.beginIndex = beginIndex; }{J>kgr6
} fWg3gRI
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/** vsA/iH.
* @return 5D^2
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* Returns the currentPage. ?gK|R
*/ :[_k .1-+
publicint getCurrentPage(){ -DZ5nx
return currentPage; j~Ci*'*L
} DvI^3 iG8
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/** N-p||u
* @param currentPage 6I]{cm
* The currentPage to set. }ew)QHd
*/ 9j;!4AJ1t
publicvoid setCurrentPage(int currentPage){ 0'5N[Bvp
this.currentPage = currentPage; s/;S2l$`
} #cJ1Jj $
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/** L`w_Q2{sv
* @return Oeg^%Y
* Returns the everyPage. .nA9irc
*/ PGTjOkx
publicint getEveryPage(){ .q 4FGPWz
return everyPage; =':SOO7
} j->5%y
2R3)/bz-SV
/** -ebyW#
* @param everyPage O+DYh=m*p
* The everyPage to set. T!&VT;
*/ d<cQYI4V
publicvoid setEveryPage(int everyPage){ |mw3v>
this.everyPage = everyPage; i|!R*"
} w0.;86<MV
M;.:YkrUH
/** \%W"KLP
* @return 0o@eE3^
* Returns the hasNextPage. |t58n{V.O
*/ cGg~+R2P
publicboolean getHasNextPage(){ m$'ZiS5
return hasNextPage; p@YbIn
} ]*rK;
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/** eN TKX
* @param hasNextPage {I$zmVG
* The hasNextPage to set. y&F&Z3t
*/ PC?XE8o
publicvoid setHasNextPage(boolean hasNextPage){ 2) Q/cH\g
this.hasNextPage = hasNextPage; Qyj:!-o
} y 5Kr<cF^
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/** KW36nY\7
* @return ph7]*W-
* Returns the hasPrePage. a0wpsl
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*/ )*BG-nM u
publicboolean getHasPrePage(){ jpiBHi]5+
return hasPrePage; CY@#_z
} Q\le3KB
#.@D}7y5
/** kbx4I?
* @param hasPrePage .Ax]SNZ+:A
* The hasPrePage to set. FCt %of#
*/ ?*f2P T?`
publicvoid setHasPrePage(boolean hasPrePage){ n--s[Kdo8
this.hasPrePage = hasPrePage; [:{HX U7y
} @PKY>58)
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/** ZlL]AD@
* @return Returns the totalPage. [_tBv" z
* mw${3j~&
*/ N*}g+IS
publicint getTotalPage(){ H7Ee0T(`
return totalPage; Yc>.P
} `Y<FR
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/** >Cglhsb:N
* @param totalPage #<R6!"TNoz
* The totalPage to set. @aWd0e]
*/ HUGhz
publicvoid setTotalPage(int totalPage){ " ,45p@
this.totalPage = totalPage; Up1e4mNL
} H')8p;~{}
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} 2Ni {fC?
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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 R\lUE,o]<q
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个PageUtil,负责对Page对象进行构造: G9ra;.
java代码: {60U6n
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/*Created on 2005-4-14*/ hyC]{E
package org.flyware.util.page; iq`caoi
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import org.apache.commons.logging.Log; J4m2|HK
import org.apache.commons.logging.LogFactory; vqJq=\ .m
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/** .arWbTR)~U
* @author Joa GsNZr=;C
* KyRcZ"
*/ /qPhptV
publicclass PageUtil { GNI:k{H@"?
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privatestaticfinal Log logger = LogFactory.getLog WKONK;U+7
}Gh95HwE
(PageUtil.class); O g!SFg*
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/** @@#h-k%k-
* Use the origin page to create a new page 6{?B`gm7g
* @param page \) g?mj^
* @param totalRecords cFloaCz
* @return 9<1dps=c
*/ q3/ 0xN+?
publicstatic Page createPage(Page page, int Xny{8Oo<1?
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F.
totalRecords){ ,^&amWey
return createPage(page.getEveryPage(), ->a|
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page.getCurrentPage(), totalRecords); h%>yErs
} (cm8x
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/**
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* the basic page utils not including exception cPPTGpqw
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handler ix_&<?8
* @param everyPage ~qezr\$2
* @param currentPage CjUYwAy$k
* @param totalRecords Yp;?Zq9
* @return page J42/S [Rt
*/ Apc!!*7
publicstatic Page createPage(int everyPage, int . MH;u3U
)i$KrN6
currentPage, int totalRecords){ ({WV<T&
everyPage = getEveryPage(everyPage); 4~z-&>%
currentPage = getCurrentPage(currentPage); H[U"eS."
int beginIndex = getBeginIndex(everyPage, NWII?X#T}
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currentPage); >|g(/@IO
int totalPage = getTotalPage(everyPage, ?dAy_|
zD
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totalRecords); sc$I,|d2
boolean hasNextPage = hasNextPage(currentPage, @ x5LrQ_`r
O#x=iZI
totalPage); oR'u&\mB
boolean hasPrePage = hasPrePage(currentPage); ^BhS*
}sW%i#CV
returnnew Page(hasPrePage, hasNextPage, &ZI-#(P
everyPage, totalPage, &r1]A&
currentPage, J3_Ou2cF`
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beginIndex); B PG&R
} WM9z~z'2a
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privatestaticint getEveryPage(int everyPage){ ZP9x3MHe
return everyPage == 0 ? 10 : everyPage; +PKd
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} 7,5Bur
CRPE:7,D
privatestaticint getCurrentPage(int currentPage){ w
L4P-4'
return currentPage == 0 ? 1 : currentPage; q0VR&b`?>D
} QfRo`l/V9
63Z^ k(
privatestaticint getBeginIndex(int everyPage, int !AN;
#N;McF;W
currentPage){ U}DLzn|w
return(currentPage - 1) * everyPage; J(w 3A)(
} :r9<wbr)k0
V{n7KhN~Y!
privatestaticint getTotalPage(int everyPage, int W(Rp@=!C
v:]z-zU
totalRecords){ S9dXkd
int totalPage = 0; QVo>Uit
3a}53?$
if(totalRecords % everyPage == 0) CI^s~M >
totalPage = totalRecords / everyPage; >Et~h65d5
else LpN3cy>U
totalPage = totalRecords / everyPage + 1 ; ;Pe=cc"@
|G/WS0
return totalPage; 2ae"Sd!-2
} <"{VVyK
}mpFo2
privatestaticboolean hasPrePage(int currentPage){ hRZYvZ3
return currentPage == 1 ? false : true; 8~y&" \
} ew<_2Xy"<
cc 0Tb
privatestaticboolean hasNextPage(int currentPage, 'PWA
@S1Z"%S
int totalPage){ Ty} Y/jW
return currentPage == totalPage || totalPage == @;}vK=6L
k5)a|
0 ? false : true; ZP'0=
} HJJ;gTj
O~mQ\GlW
2WC$r8E
} *U +<Hv`C
jc HyRR1R
lcK4 Uq\q
0[E\h
7MQh,J!"
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 &z@}9U*6b
I>{o]^xw-D
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 U7HfDDh
OAf}\
做法如下: [ps4i_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 |G_, 1$
l2ie\4dK@
的信息,和一个结果集List: 2"_5Yyb
java代码: *Sps^Wl
O_L>We@3E
a[p$e?gka
/*Created on 2005-6-13*/ tXcZl!3x
package com.adt.bo; s"R5'W\U
S_?sJwM
import java.util.List; Po*!eD
n'[>h0
import org.flyware.util.page.Page; 6sG5n7E-A
xxA^A
/** w |abaMam
* @author Joa 7^tYtMm|U
*/ \&47u1B
publicclass Result { aJ}hlM>
oU se~
private Page page; Q]e]\J
@km4qJZ
private List content; 2_}oOt?qiM
LXaq
/** @saK:z
* The default constructor @WNqD*)1
*/ Gn<0Fy2
public Result(){ 5p6/dlN-a
super(); f3S 8~!
} '2
Y8
o`G6!
/** -ijzo%&qA
* The constructor using fields q;*'V9#
* ESUO I
* @param page (4?^X
* @param content =cO5Nt
*/ ?d+ri
public Result(Page page, List content){ [5tvdW6Z&
this.page = page; A1r%cs
this.content = content; "!CVm{7[
} K+"3He
HJBGxyw
/** N3N~z1x0h
* @return Returns the content. xojt s;n
*/ Mdq|:^px
publicList getContent(){ Kwi+}B!
return content; UA4c4~$S
} (V1;`sI8
w 62m}5eA
/** aRElk&M
* @return Returns the page. t2Jf+t_B7
*/ %!eRR
public Page getPage(){ %|D)U>o{
return page; -}PE(c1%?q
} #RbdQH !
vG7Mk8mIr
/** 1rs.
* @param content ay|jq"a
* The content to set. <B>hvuCoH
*/ w}#3 pU<<
public void setContent(List content){ UBJYs{zz
this.content = content; W?"l6s
} ?XP4kjJ
P(DEf(
/** ![$`Ivro`
* @param page [+QyKyhTO
* The page to set. `wZ
*/ Hzj8o3
publicvoid setPage(Page page){ Ghc
U~
this.page = page;
+ K`.ck
} @3$ I
} JZ+6)R
Vr Lp5?Bh
$gN\%X/n"1
_>n)HG
4f~sRubK
2. 编写业务逻辑接口,并实现它(UserManager, mZc; n.$U
*C0a,G4
UserManagerImpl) 8EMBqhl
java代码: cvo+{u$s
dNY'uv&Y
Thu_`QP^
/*Created on 2005-7-15*/ ~5h4 Gy)
package com.adt.service; =+ b>d\7xG
,X1M!'
import net.sf.hibernate.HibernateException; (X-(
WMsqQ
]f?r@U'AS|
import org.flyware.util.page.Page; 7)[2Ud8
uF1 4;
import com.adt.bo.Result; UJQTArf
6rj iZ%
/** }st~$JsV1
* @author Joa I\1"E y
*/ 9C2pGfEbn}
publicinterface UserManager { M$Ui=GGq
"U"fsAc#
public Result listUser(Page page)throws 0^\H$An*k
e$P^},0/
HibernateException; TB?'<hD:
SXYwhID=
} &WLN
R9^vAS4t[O
H\n6t-l
DTuco9yr[
H ?9Bo!
java代码: ;dMr2y`6
jA;b2A]G
W1<*9O
/*Created on 2005-7-15*/ ^|6#Vx
package com.adt.service.impl; YpXd5;'
`GBJa k
import java.util.List; ,jeHL@>w[
74:( -vS
import net.sf.hibernate.HibernateException; \m}a%/
<}A6 )=T
import org.flyware.util.page.Page; N\&VJc
import org.flyware.util.page.PageUtil; 2;*G!rE&*`
0tL5t7/Gr
import com.adt.bo.Result; ks("(
nU
import com.adt.dao.UserDAO; wJJ|]^0.
import com.adt.exception.ObjectNotFoundException; p>\[[Md
import com.adt.service.UserManager; /m;Bwu
A^+k A)8
/** -T1R}ew*t
* @author Joa l3BN,HNv+
*/ u/wX7s
publicclass UserManagerImpl implements UserManager { s.rQiD
xzA!,75@U
private UserDAO userDAO; &&52ji<3
h$$JXf
/** R[6R)#o
* @param userDAO The userDAO to set. r}e(MT:R'
*/ Q?LzL(OioN
publicvoid setUserDAO(UserDAO userDAO){ lH`c&LL-=!
this.userDAO = userDAO; "Dk@-Ac
} ^Ss<<
PPrvVGP
/* (non-Javadoc) ewN|">WXQ
* @see com.adt.service.UserManager#listUser bv(+$YR
0%,W5w
(org.flyware.util.page.Page) YfZ5Q}*1O+
*/ ib
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public Result listUser(Page page)throws 2-qWR<E
*y|w9rp
HibernateException, ObjectNotFoundException { c)N_"#&
int totalRecords = userDAO.getUserCount(); ZVJ6 {DS/
if(totalRecords == 0) "QS(4yw?jg
throw new ObjectNotFoundException g8&& W_BI
7Dl^5q.|
("userNotExist"); }id)~h_@
page = PageUtil.createPage(page, totalRecords); I]5){Q"S
List users = userDAO.getUserByPage(page); h(}#s1Fzq
returnnew Result(page, users); >
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} H(--hG5}
u81F^72U
} {yT<22Fl
8KigGhY'ms
+/%4E %
DwFvM0O6\
)>b1%x} =
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5N6R%2,A
]Hi1^Y<
询,接下来编写UserDAO的代码: NcwUK\
3. UserDAO 和 UserDAOImpl: "30=!k
java代码: [:e>FXV
y6sY?uu
Yz0HBEA
/*Created on 2005-7-15*/ bOrE86v:
package com.adt.dao; yGWl8\,j0
s5{H15
import java.util.List; JUDZ_cGr
j!Ys/D
import org.flyware.util.page.Page; SI%J+Y7
SJj_e-
import net.sf.hibernate.HibernateException; #=Xa(<t
ujX\^c
/** 2++$ Ql/
* @author Joa 2fc+PE
*/ { i3x\|
publicinterface UserDAO extends BaseDAO { <b\.d^=B
GpO@1 C/
publicList getUserByName(String name)throws !f/^1k}SR
wT;;B=u}G
HibernateException; ]k1N-/
o!y<:CGL
publicint getUserCount()throws HibernateException; AlrUfSBB
WRAv>s9
publicList getUserByPage(Page page)throws >[T6/#M
}c4F}Cy
HibernateException; uF|[MWcy0#
+U<Ae^V
} S*3$1BTl
4T&Jlu?:
p{r{}iYI
R~TG5^(
b^8"EBo
java代码: _Bn8i(
k^k1>F}yx
(lit^v,9
/*Created on 2005-7-15*/ biffBC:q
package com.adt.dao.impl; ahM?;p
c-@EHv
import java.util.List; pAN$c"
T%}x%9VO7
import org.flyware.util.page.Page; +{)V%"{u:
|?'
gT"#
import net.sf.hibernate.HibernateException; vl%Pg!l
import net.sf.hibernate.Query; ^MT20pL
Dn~t _n
import com.adt.dao.UserDAO; &|zV Wl
5KYR"-jY
/** a,M/i&.e`
* @author Joa mn{R>
*/ Xa>c]j
public class UserDAOImpl extends BaseDAOHibernateImpl RhjU^,%
S |@
Y !
implements UserDAO { 7#T@CKdUd
&.0 wPyw
/* (non-Javadoc) ROfke.N\'
* @see com.adt.dao.UserDAO#getUserByName a5@lWpQsV
9x8Ai
(java.lang.String) | 8n,|%e
*/ yAel4b/}
publicList getUserByName(String name)throws 0b,{4DOD
{`L,F
HibernateException { !:g\Fe]
String querySentence = "FROM user in class 1tpt433
*(*XNd||
com.adt.po.User WHERE user.name=:name"; .8|5;!`WB
Query query = getSession().createQuery '+S!>Lqb
<@@@Pl!~
(querySentence); +w@/$datI
query.setParameter("name", name); .M\0+,%/
return query.list(); *OKve
} =&U7:u
VN@ZYSs
/* (non-Javadoc) 5hiuBf<
* @see com.adt.dao.UserDAO#getUserCount() zjx'nK{eI
*/ QO,ge<N+N
publicint getUserCount()throws HibernateException { .7#04_aP
int count = 0; =OA7$z[
String querySentence = "SELECT count(*) FROM LA837%)
C9T-4o1
user in class com.adt.po.User"; gD6BPW~0
Query query = getSession().createQuery Rmh,P >
<,T#* fg
(querySentence); @eDL j}
count = ((Integer)query.iterate().next )#cGePA
>LR+dShG
()).intValue(); BQ~&gy{
return count; v{U1B
} umiD2BRZ
`&/ zOMp
/* (non-Javadoc) C1~Ro9si
* @see com.adt.dao.UserDAO#getUserByPage LGVGr
Tj=g[)+K
(org.flyware.util.page.Page) GwlAEh P
*/ cFG%Ew@
publicList getUserByPage(Page page)throws ;\+A6(GX{
*icxK
HibernateException { rMUQh~a/
String querySentence = "FROM user in class `qbsDfq@
Tq >?.bq9
com.adt.po.User"; JvLa@E)
Query query = getSession().createQuery :cTwp K
Dr"F5Wbg
(querySentence); gB#$"mq,
query.setFirstResult(page.getBeginIndex()) ~48mCD
.setMaxResults(page.getEveryPage()); TqMy">>
return query.list(); 4dvuw{NZ
} V6
,59
gLv";"4S
} .J|"bs9
^`!EpO>k9
o"A%dC_
YPav5<{a
P}Ul e|&LK
至此,一个完整的分页程序完成。前台的只需要调用 5 %aT
$;+`sVG
userManager.listUser(page)即可得到一个Page对象和结果集对象 o//PlG~
V0
OT _F
的综合体,而传入的参数page对象则可以由前台传入,如果用 jvos)$;L-
C0Ti9
webwork,甚至可以直接在配置文件中指定。 ldm=uW
NvlG@^&S
下面给出一个webwork调用示例: !.k
java代码: y3C$%yv0
[mk!]r
X*C4NF0
/*Created on 2005-6-17*/ F%QVn.
package com.adt.action.user; Ndx ]5
%S4pkFR
import java.util.List; -T-h~5
CpICb9w
import org.apache.commons.logging.Log; )<jT;cT!&
import org.apache.commons.logging.LogFactory; +Gvf5+ 5VR
import org.flyware.util.page.Page; M3dNG]3E
enJE#4Z5&s
import com.adt.bo.Result; (@?PN+68|
import com.adt.service.UserService; N;\by<snN
import com.opensymphony.xwork.Action; @7';bfsix
fM)R O7
/** R|AGN*.
* @author Joa e[8p /hId
*/ "^ cn9AG{
publicclass ListUser implementsAction{ a|@^N
. RNQlh3
privatestaticfinal Log logger = LogFactory.getLog SQbnn"
yN~: 3
(ListUser.class); Jk7[}Jc$
vg1p{^N!
private UserService userService; E8Wgm
8
KArnNmJ9
private Page page; eESJk14
-3c?Yaf"
privateList users; 5fBW#6N/
hU `H\LE
/* R3$eq
)
* (non-Javadoc) 2$? )VXtw
* =lG5Kc{B
* @see com.opensymphony.xwork.Action#execute() 8f |
*/ 8ESBui3;
publicString execute()throwsException{ l$Y7CIH
Result result = userService.listUser(page); A{hWFSv
page = result.getPage(); >c7fg^@
users = result.getContent(); vf(\?Js,
return SUCCESS; kqA`d
} `r iK[@
( UV8M\
/** s?5(E}
* @return Returns the page. p]#%e0
*/ /\_ s
public Page getPage(){ B;':Eaa@
return page; 4jrY3gyBX
} ,.fGZ4
cQUmcK/,
/** 8<6;X7<-
* @return Returns the users. PhM3?$
*/ nK6{_Y>
publicList getUsers(){ (a1 s~
return users; 7{XI^I:n
} z@biX
I"9S
/** !UlG!820
* @param page *B`wQhB%
* The page to set. [3rvRJ.
*/ V5RfxWtm:
publicvoid setPage(Page page){ ek#{!9-
this.page = page; [>4Ou^=1
} 1<
;<?
F\&R nDJ
/** h 5ST`jZ
* @param users z}N=Oe
* The users to set. BfIGw
*/ -2mm
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publicvoid setUsers(List users){ QE$sXP7&u
this.users = users; Ry0n_J:7
} zrG&p Z
_Y*]'?g`
/** 5+'1 :Sa(i
* @param userService Rg,pC.7;
* The userService to set. _w=si?q
*/ 'cT R<LVo
publicvoid setUserService(UserService userService){ $v+Q~\'
this.userService = userService; N'!a{rF
}
F\Ex$:%~
} =\?KC)F*e
BD9W-mF
{(AYs*5
'ac %]}`-
M"#xjP.
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, -D0kp~AO4N
*<zfe.
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 Sim\+SL{#
}^^X-_XT
么只需要: 0S;H`w_S
java代码: INE8@}e
-Yy,L%E]F:
;+`t[ go
<?xml version="1.0"?> z'JtH^^Z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork kA{[k
Uo<d]4p $
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +glT5sOk
[&y{z-D>
1.0.dtd"> o4,W!^n2
kf>oZ*/
<xwork> a8FC#kfq
xf?*fm?m
<package name="user" extends="webwork- Y'`w.+9
CYmwT>P+*4
interceptors"> {xp/1?Mo*
vZmM=hW ~
<!-- The default interceptor stack name U|={LU
#)2'I`_E
--> 3VbMW, _&"
<default-interceptor-ref gN
Xg
b'4{l[3~nl
name="myDefaultWebStack"/> {Tl5,CAz
?k]^?7GN
<action name="listUser" B)O{+avu
(hS
j4Cp
class="com.adt.action.user.ListUser"> Tf)qd\
<param K 38e,O
)'KkO$^&
name="page.everyPage">10</param> \m~?mg"#
<result 61HU_!A8S
iF?4G^
name="success">/user/user_list.jsp</result> \L-o>O
</action> eYMp@Cx
0
Ji>drn
</package> ^+^#KC8]W
anjU3j
</xwork> x4Mq{MrWp
p?2\9C4
U6e 0{n
}eetx68\
BMkN68q
@r^a/]5D
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 9aFu51
+]
>o@
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。 Tz[ck'k
[QEV6S]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 \wEHYz
c"Ddw'?e
OOn{Wp
)-%3;e<w
lk]q\yO_%
我写的一个用于分页的类,用了泛型了,hoho eW,{E)x:
HjAhz
java代码: 4t]ccqX*{
'hN_H}U
mN?y\GB
package com.intokr.util; vg[A/$gLM
Zvz Zs
import java.util.List; Jw3VWc
]]
UKV0xl
/** m r"b/oM{
* 用于分页的类<br> Z:9xf:g*
* 可以用于传递查询的结果也可以用于传送查询的参数<br> o{7wPwQ;*
*
n@xC?D:t*
* @version 0.01 Y S/x;
* @author cheng jD1/`g%
*/ ;c p*]
public class Paginator<E> { 'c7C*6;a
privateint count = 0; // 总记录数 /k8Lu+OJ
privateint p = 1; // 页编号 .}!"J`{W
privateint num = 20; // 每页的记录数 Z"j #kaXA
privateList<E> results = null; // 结果 p5`iq~e9
[qbZp1s|(
/** 4&%0%
* 结果总数 ,Ta k',
*/ B;x5os
publicint getCount(){ pURtk-Fr2
return count; WxLbf+0o
} M3 MB{cA2
""$vaqt
publicvoid setCount(int count){ g>`
k9`
this.count = count; LtIp,2GP&_
} *-uA\
uH*moVw@5
/** $eHYy,,
* 本结果所在的页码,从1开始 }C-K0ba7
* .n$c+{
* @return Returns the pageNo. U9"g;t+/
*/ FM$$0}X
publicint getP(){ jN))|eD0x
return p; _L?MYkD
} (D2G.R\pr
S$#"bK/p^
/** t5O '7x
* if(p<=0) p=1 8/W(jVO(-
* pmda9V4
* @param p nv$>iJ^~H
*/ 5j'7V1:2
publicvoid setP(int p){ WB)pE'5
if(p <= 0) R!&9RvNw
p = 1; 8XfhXm>~
this.p = p; atr0hmQ
} u@&e{w~0
0O>T{<
/** U]/iPG&_
* 每页记录数量 "x1?T+j4
*/ Me;XG?`
publicint getNum(){ /q1k)4?E
return num; N+lhztYQ?
} eX`wQoV%
}2xgm9j<
/** ?D>%+rK8c
* if(num<1) num=1 >EE}P|=-
*/ M./1.k&@
publicvoid setNum(int num){ /{6&99SJcc
if(num < 1) &t)$5\r
num = 1; jVlXB6[-
this.num = num; ,~Y[XazT
} ]@Z[/z%~04
r:{;HM+
/** oYx4+xH/
* 获得总页数 Ml,~@}
p
*/ --OAsbr
publicint getPageNum(){ ._%8H
return(count - 1) / num + 1; Jb/VITqN4
} @LSfP
B:)PUBb
/** P5Bva
* 获得本页的开始编号,为 (p-1)*num+1 G*s5GG@Z.
*/ hTc
:'vq
publicint getStart(){ +MR]h
[
return(p - 1) * num + 1; xig4H7V
} q$7w?(Lk
[n]C
/** Six2{b)p
* @return Returns the results. xs
1V?0
*/ SA{noM
publicList<E> getResults(){ :|\[a0ZL
return results; Cl6P,C
} `y3*\l
mX/'Fta
public void setResults(List<E> results){ 0g8ykGyx
this.results = results; \B4f5L8k
} _<Ip0?N
U|
T}0
public String toString(){ k1'd';gQ
StringBuilder buff = new StringBuilder wY]ejK$0R
`\beQ(g
(); bblEZ%
buff.append("{"); t5CJG '!ql
buff.append("count:").append(count); .TeGA;
buff.append(",p:").append(p); /&N\#;kK?b
buff.append(",nump:").append(num); 5X PoQ^
buff.append(",results:").append 5Lm-KohT'
;.66phe
(results); :]icW^%
buff.append("}"); aH7@:=B
return buff.toString(); G>edJPfQ
} QsX`IYk
:jAsm[
} :FUxe kz
Qo/pz2N
.PD_Vv>C/>