Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 238z'I+$G/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 84s:cO
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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 PWfd<Yf!
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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 W9bpKmc
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分页支持类: :K(+ KN(
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java代码: k9c`[M
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package com.javaeye.common.util; }/g1
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import java.util.List; Yi19VU|/
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publicclass PaginationSupport {
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publicfinalstaticint PAGESIZE = 30; E.^u:0:P
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privateint pageSize = PAGESIZE; $]?M[sL\N7
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privateList items; dQ#oY|a
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privateint totalCount; lg
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privateint[] indexes = newint[0]; %*Yb
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privateint startIndex = 0; uiWo<}t}{
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public PaginationSupport(List items, int VY0-18 o
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totalCount){ T'N/A9{q
setPageSize(PAGESIZE); v,US4C|^3i
setTotalCount(totalCount); g=Nde2d?
setItems(items); ;3Q3!+%j
setStartIndex(0); P+ 0-h
} cQ0+kX<
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public PaginationSupport(List items, int SWNT}{x]
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totalCount, int startIndex){ ZZ>(o
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setPageSize(PAGESIZE); u#3Cst8Y
setTotalCount(totalCount); vQ{mEaH
setItems(items); )xTu|V
setStartIndex(startIndex); R5<:3tk=X
} |lVi* 4za%
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public PaginationSupport(List items, int gNh4c{Al9
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totalCount, int pageSize, int startIndex){ $- GwNG
setPageSize(pageSize); mf2Qu
setTotalCount(totalCount); ]YB,K)WQ
setItems(items); ~sCdvBA
setStartIndex(startIndex); :}o{<U
} zZ8:>2Ps(
X
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publicList getItems(){ 2JHV*/Q
return items; !'=<uU-
} i"{znKz vD
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publicvoid setItems(List items){ Jz-RMX=
this.items = items; 5"Y:^_8
} hP
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publicint getPageSize(){ ~VPE9D@
return pageSize; `L.nj6F
} Lvn+EM
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publicvoid setPageSize(int pageSize){ q)tNH/
this.pageSize = pageSize; S#\Cyn2(t
} 59(} D'lw>
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publicint getTotalCount(){ :n oZ
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return totalCount; ,go$6
} Vv>hr+e
@DyMq3Gt?&
publicvoid setTotalCount(int totalCount){ g<i>252>
if(totalCount > 0){ [ _&z+
this.totalCount = totalCount; YKa9]Q
int count = totalCount / Qs_]U
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pageSize; vz)zl2F5sY
if(totalCount % pageSize > 0) ^i17MvT'
count++; tSaD=# v
indexes = newint[count]; 1(
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for(int i = 0; i < count; i++){ H(Ad"1~.#
indexes = pageSize * _(KzjOMt
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i; q}J Eesf
} /qXP\ a
}else{ E_K32)J-
this.totalCount = 0; zHvW@A'F
} .H5^ N\V|
} 4HyD=6V#
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publicint[] getIndexes(){ ,v(ikPzd
return indexes; hj3wxH.}
} iD:TKB_r
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publicvoid setIndexes(int[] indexes){ }M9I]\
this.indexes = indexes; (vbI4&r
} >):>Pz%U
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publicint getStartIndex(){ E}|IU Pm
return startIndex; UFr5'T
} vt}A6mF
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publicvoid setStartIndex(int startIndex){ M V~3~h8
if(totalCount <= 0) .IORvP-M&
this.startIndex = 0; f_> lz
elseif(startIndex >= totalCount) eo4v[V&
this.startIndex = indexes p 4l B#
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[indexes.length - 1]; 4J2C#Cs
elseif(startIndex < 0) O4,?C)
this.startIndex = 0; NQ\<~a`Eq
else{ :z+l=d:4
this.startIndex = indexes 7]8apei|
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[startIndex / pageSize]; Gv6#LcF#
} k)S'@>n{u
} _(:bGI'.m
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publicint getNextIndex(){ Iz I
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int nextIndex = getStartIndex() + lkgB,cflpi
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pageSize; Us8nOr>5
if(nextIndex >= totalCount) ?) VBkA5j
return getStartIndex(); l~GcD
else 6"jV>CNc@
return nextIndex; f15n ~d
} I sB=G-s
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publicint getPreviousIndex(){ uJL[m(G
int previousIndex = getStartIndex() - Z~DR,:
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pageSize; Uj>bWa`
if(previousIndex < 0) =7<g;u
return0; Blv@u ?
else -<aN$O
return previousIndex; -{S:sK.o
} T3^(I~03
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} l\~F0Z/O
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抽象业务类 !"N-To-c
java代码: UWq[K&vQZ
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/** M`.v/UQn
* Created on 2005-7-12 {~eVZVv
*/ %n>*jFC
package com.javaeye.common.business; L2^M#G@t
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import java.io.Serializable; mEDi'!YE"
import java.util.List; l*<RKY8
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import org.hibernate.Criteria; +(J{~A~
import org.hibernate.HibernateException; SHP_
import org.hibernate.Session; ER*Et+>
import org.hibernate.criterion.DetachedCriteria; S%k](\7!
import org.hibernate.criterion.Projections; 8zk?:?8%{
import B&c*KaK;~
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org.springframework.orm.hibernate3.HibernateCallback; \*6Ld%:h$
import :sXn*k4v
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org.springframework.orm.hibernate3.support.HibernateDaoS B]5G"4,
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upport; h;2n2.Q
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import com.javaeye.common.util.PaginationSupport; MLn \b0
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public abstract class AbstractManager extends k\wI^D
@EzO
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HibernateDaoSupport { 2/V9Or52
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privateboolean cacheQueries = false; gN/6%,H}
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privateString queryCacheRegion; \*k}RKDwT
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publicvoid setCacheQueries(boolean <hSrx7o
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cacheQueries){ nA>kJSL'$
this.cacheQueries = cacheQueries; [`Dv#
} .3yxg}E>{
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publicvoid setQueryCacheRegion(String Q,z^eMk'd:
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queryCacheRegion){ 0NMekVi
this.queryCacheRegion = *FrlzIAom
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queryCacheRegion; 1lLL9l{UVw
} 0413K_
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publicvoid save(finalObject entity){ Z
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getHibernateTemplate().save(entity); Y]gb`z$?
} sM$gfFx
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publicvoid persist(finalObject entity){ a+Z95~*sZ"
getHibernateTemplate().save(entity); ?A7_&=J%
} #^~[\8v>
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publicvoid update(finalObject entity){ (:2,Rr1"
getHibernateTemplate().update(entity); `cBV+00YS
} m?Qr)F_M
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publicvoid delete(finalObject entity){ `$odxo+
getHibernateTemplate().delete(entity); G 0;5I_D/
} dy%#E2f
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publicObject load(finalClass entity, NWq>Z!x`
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finalSerializable id){ "=97:H{!
return getHibernateTemplate().load OPsg3pW!]
PA(XdT{
(entity, id); Vx6/Rehj
} B5Y
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publicObject get(finalClass entity, D-<9kBZs
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finalSerializable id){ RiX~YLeM
return getHibernateTemplate().get Ow\dk^\-G8
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(entity, id); g:sn/Zug]
} 6*n<emP
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publicList findAll(finalClass entity){ zrg#BXj7
return getHibernateTemplate().find("from _b8?_Zq
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" + entity.getName()); \Gk4J<
} E8=8OX/{Y
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publicList findByNamedQuery(finalString s;'jn_,0
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namedQuery){ ]_ WB^
return getHibernateTemplate _z$lg]q
sm~{fg
().findByNamedQuery(namedQuery); B8'e,9
} "5,tEP!
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publicList findByNamedQuery(finalString query, <[eE5X(
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finalObject parameter){ v0yaFP#kG
return getHibernateTemplate ?zD?-
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().findByNamedQuery(query, parameter); K9YD)351t
} '9Hah
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publicList findByNamedQuery(finalString query, 8 N5ga
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finalObject[] parameters){ K5fL{2V?
return getHibernateTemplate IP 9{vk
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().findByNamedQuery(query, parameters); 'F- wC!
} K38A;=t9
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publicList find(finalString query){ EN =oA P
return getHibernateTemplate().find 0=2D90
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(query); 8Q%rBl.
} J4-64t nZ
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publicList find(finalString query, finalObject KfO$bmwmx
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parameter){ &{Zt(%\ '
return getHibernateTemplate().find ,&1DKx
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(query, parameter); &3Q!'pJJ
} j}2,|9ne
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public PaginationSupport findPageByCriteria 5f:Mb|.?
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(final DetachedCriteria detachedCriteria){ me+F0:L
return findPageByCriteria =2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @o[C
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} X_}2xo|T
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public PaginationSupport findPageByCriteria \m3;<A/3n
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(final DetachedCriteria detachedCriteria, finalint Iq@: n_~
:+9KNyA
startIndex){ d Q5_=(9
return findPageByCriteria -gWqq7O
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(detachedCriteria, PaginationSupport.PAGESIZE, #sn2Vmi
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startIndex); SA| AS<
} N6"b
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public PaginationSupport findPageByCriteria "pDwN$c
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(final DetachedCriteria detachedCriteria, finalint FY^[?lj
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pageSize, SD "'
finalint startIndex){ 7>Af"1$g
return(PaginationSupport) u*I=.
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getHibernateTemplate().execute(new HibernateCallback(){ MT8BP)C
publicObject doInHibernate jIq@@8 @o
^ di[J^
(Session session)throws HibernateException { ;\F3~rl
Criteria criteria = CnJrJ>l
@A_bZQ@
detachedCriteria.getExecutableCriteria(session); DriJn`vtzq
int totalCount = mG?g
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((Integer) criteria.setProjection(Projections.rowCount ,X[lC\1a
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()).uniqueResult()).intValue(); {&2aH>V/
criteria.setProjection Q-3o k7
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(null); R. sRH/6
List items = {9tKq--@E9
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criteria.setFirstResult(startIndex).setMaxResults F__j]}?
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(pageSize).list(); @l7~Zn
PaginationSupport ps = HA?<j|M
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new PaginationSupport(items, totalCount, pageSize, 7~2b4"&
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startIndex); tgy= .o]
return ps; IXm}WTgF!
} G@YX8!wU
}, true); V
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} #1INOR9
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public List findAllByCriteria(final j-egsKR
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DetachedCriteria detachedCriteria){ or?@Ti;
return(List) getHibernateTemplate Vv"JN?dHi
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().execute(new HibernateCallback(){ LL|uMe"Jb
publicObject doInHibernate mE`OG8
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(Session session)throws HibernateException { pvCf4pf~
Criteria criteria = T6gugDQ~.
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detachedCriteria.getExecutableCriteria(session); zYCrfr
return criteria.list(); :[;]6;
} F/MzrK\':m
}, true); &+@~;p5F
} f`zH#{u
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public int getCountByCriteria(final MIblx
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DetachedCriteria detachedCriteria){ CdxEY
Integer count = (Integer) 4eZ
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getHibernateTemplate().execute(new HibernateCallback(){ [(Z sQK
publicObject doInHibernate T=/GFg'
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(Session session)throws HibernateException { 'hTAO1n8
Criteria criteria = rTBrl[&,q'
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detachedCriteria.getExecutableCriteria(session); n|t?MoUP
return mlIX>ss|7B
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criteria.setProjection(Projections.rowCount c4]/{!4 Q
$$UMc-Pq
()).uniqueResult(); Who7{|M\'
} \E9Hk{V:6
}, true); 28 h3Ayw4
return count.intValue(); XS$5TNI
} U>0' K3_
} x$G u)S
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用户在web层构造查询条件detachedCriteria,和可选的 ls5s}X
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 \,:3bY_d
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PaginationSupport的实例ps。 oSmv
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ps.getItems()得到已分页好的结果集 $U,`M"
ps.getIndexes()得到分页索引的数组 8vzjPWu
ps.getTotalCount()得到总结果数 eY3l^Su1
ps.getStartIndex()当前分页索引 3|$>2IRq
ps.getNextIndex()下一页索引 1!u}~E_
ps.getPreviousIndex()上一页索引 ',?9\xEB
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ('!{kVLT-
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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 q#fj?`k
]dZ8]I<$C
一下代码重构了。 $"P9I-\m
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我把原本我的做法也提供出来供大家讨论吧: f1cQ*#2~
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首先,为了实现分页查询,我封装了一个Page类: g+5{&YD
java代码: zzf;3S?
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/*Created on 2005-4-14*/ wzX
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package org.flyware.util.page; ("2ukHc
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/** dXAKk[uf
* @author Joa Kjbz\~
* y`"~zq0D
*/ ~7Ji+AJA
publicclass Page { :D-xa!7
T*,kBJ
/** imply if the page has previous page */ */=5m]
privateboolean hasPrePage; a );>
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/** imply if the page has next page */ .C
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privateboolean hasNextPage; n^8LF9r
#;Yn8'a~
/** the number of every page */ u{0'"jVJ
privateint everyPage; hkzyI~7
%9z N U
/** the total page number */ 7U#`^Q}
privateint totalPage; 8 *@knkJ
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/** the number of current page */ <8UqV.&
privateint currentPage; VGbuEC [Y
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/** the begin index of the records by the current #qk}e4u
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query */ DKV^c'
privateint beginIndex; $gi{)'z
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/** The default constructor */ zk+&5d4(
public Page(){ |*4)G6J@n
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} \cq
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/** construct the page by everyPage iz'#K?PF_
* @param everyPage } D5*
* */ qaBjV6loy
public Page(int everyPage){ &KfRZ`9H
this.everyPage = everyPage; #JAU5d
} 1tvgM
!.
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/** The whole constructor */ >G`=8Ku
public Page(boolean hasPrePage, boolean hasNextPage, (k?,+jnR
4l! ^"=rh
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int everyPage, int totalPage, xyO]Evg
int currentPage, int beginIndex){ K*uFqdLL!
this.hasPrePage = hasPrePage; k0|*8
this.hasNextPage = hasNextPage; h:QKd!Gq
this.everyPage = everyPage; *uYnu|UQH
this.totalPage = totalPage; q2VQS1R`8
this.currentPage = currentPage; 'jp nQcwxx
this.beginIndex = beginIndex; w$J0/eX{A
} 8fpaY{]
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/** iE}jilU
* @return S[fzy$">
* Returns the beginIndex. ]A}'jP
*/ hw`+,_ g
publicint getBeginIndex(){ 6x\+j
return beginIndex; jd;=5(2
} F^kH"u[
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/** C3fSSa%b
* @param beginIndex ${n=1-SMU
* The beginIndex to set. xZ2}1D
*/ w yO@oi
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publicvoid setBeginIndex(int beginIndex){ XAuB .)|
this.beginIndex = beginIndex; Ya] qo]
} b&u o^G,
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/** <wwcPe}
* @return 3 wVN:g7
* Returns the currentPage. kq6K<e4jO
*/ 0dhJ# [Y
publicint getCurrentPage(){ ZOl
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return currentPage; 9OB[ig
} 2#Fc4RR;
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/** {.9phW4Vr?
* @param currentPage jRXpEiM
* The currentPage to set. y4`<$gL
*/
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publicvoid setCurrentPage(int currentPage){ Ww*='lz
this.currentPage = currentPage; j3QpY9A
} ocwRU0+j
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/** h'wOslyFa
* @return YIA}F1:
* Returns the everyPage. wC@5[e$
*/ }'{39vc .
publicint getEveryPage(){ P>%\pCJ])
return everyPage; S5ka;g
} Xz5 aTJ&
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/**
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* @param everyPage DB'pRo+U
* The everyPage to set. G.K3'^_
*/ <Gzy*1Q&
publicvoid setEveryPage(int everyPage){ m`UNdFS
this.everyPage = everyPage; Z~o*$tF/
} )AOD~T4s7
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/** 0N.tPF}
* @return WAiEINQ^)
* Returns the hasNextPage. SymSAq0$F
*/ mg)lr&-b
publicboolean getHasNextPage(){ .:,RoK1
return hasNextPage; lpkg(J#&
} T{u!4Yu
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/** LH..8nfl
* @param hasNextPage e47JLW&b
* The hasNextPage to set. le`&VdE^
*/ ((rk)Q+;v
publicvoid setHasNextPage(boolean hasNextPage){ N m-{$U
this.hasNextPage = hasNextPage; VY8p[`
} z^9Yoqog
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/** th8f
* @return b3e:F{n
^
* Returns the hasPrePage. Y4`MgP8t
*/ NLM ]KT
publicboolean getHasPrePage(){ ay#cW.,
return hasPrePage; -bo2"*|m
} NtMK+y
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/** &NV[)6!
* @param hasPrePage (5?5? <
* The hasPrePage to set. Okca6=2"
*/ 0B)l"$W[)/
publicvoid setHasPrePage(boolean hasPrePage){ #"d.D7nA
this.hasPrePage = hasPrePage; d
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} _GK^ 7}u
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/** ZC3b9:tk
* @return Returns the totalPage. 4*OL^\%
* vOsd>3"
*/ v,r}q1.E}
publicint getTotalPage(){ xEaRuH c
return totalPage; i7 `dY{p7
} R3F>"(P@tS
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/** Ea1{9>S
* @param totalPage "+s#!Fh *
* The totalPage to set. *w4jE T>
*/ ,.tT9?
m
publicvoid setTotalPage(int totalPage){ EDvK9J
this.totalPage = totalPage; &$ F0
} ayyn6a8
A|tee@H*0
} La?q>
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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 C1P{4 U
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个PageUtil,负责对Page对象进行构造: 1Nw&Z0MI
java代码: ?UQVmE&
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/*Created on 2005-4-14*/ #/@U|g
package org.flyware.util.page; ([UuO}m-
AL! ^1hCF
import org.apache.commons.logging.Log; c&)H
import org.apache.commons.logging.LogFactory; $G5m/[KDI
j11 \t
/** ,Ihuo5>/z
* @author Joa [6BLC{2
* /7*jH2
*/ lO8.Q"mxo
publicclass PageUtil { F1R91V|
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privatestaticfinal Log logger = LogFactory.getLog %@ $h?HP
`3kE$h#
(PageUtil.class); Y\BB;"x1
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/** RGhl`;
* Use the origin page to create a new page #h ;j2
* @param page F
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* @param totalRecords _`/0/69
* @return wQ!~c2a<8
*/ ~wDmt
publicstatic Page createPage(Page page, int |K'{R'A
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totalRecords){ m(nlu
return createPage(page.getEveryPage(), [{N
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page.getCurrentPage(), totalRecords); u_@%}zo?5*
} yk#yrxM
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/** l7aGo1TcIh
* the basic page utils not including exception 0{v?
{b^naE
handler [ar:zlV8
* @param everyPage 4DEsB)%X
* @param currentPage cGkl=-oQ'
* @param totalRecords R%aH{UhE`
* @return page b@^M|h.Va
*/ lZ0+:DaP2
publicstatic Page createPage(int everyPage, int 52m^jT Sx
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currentPage, int totalRecords){ a%tm[Re
everyPage = getEveryPage(everyPage); `NXyzT`:K
currentPage = getCurrentPage(currentPage); jp8=>mk
int beginIndex = getBeginIndex(everyPage, m<8j' [+
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currentPage); %2BFbaE
int totalPage = getTotalPage(everyPage, yZK1bnYG|I
k(=\&T
totalRecords); @5
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boolean hasNextPage = hasNextPage(currentPage, 9/}i6j8Z
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totalPage); =G}_PRn
boolean hasPrePage = hasPrePage(currentPage); =/6.4;8
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returnnew Page(hasPrePage, hasNextPage, E2(;R!ML#
everyPage, totalPage, -c<<A.X
currentPage, ="@W)"r
1?(BWX)7
beginIndex); Qu!\Cx@
} <tf4j3lwH
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privatestaticint getEveryPage(int everyPage){ {,IWjt &>
return everyPage == 0 ? 10 : everyPage; ?MKf=!w
} P)1@HDN==
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privatestaticint getCurrentPage(int currentPage){ f*XF"@ZQV
return currentPage == 0 ? 1 : currentPage; z$7YC49^
} edGV[=]F
TzPx4L6?
privatestaticint getBeginIndex(int everyPage, int j`,;J[Zd`h
Hxb{bF
currentPage){ ;T#t)oV
return(currentPage - 1) * everyPage; k%hD<_:p
} E|97zc
P|h<|Gcp
privatestaticint getTotalPage(int everyPage, int OOl{
Da-F(^E
totalRecords){ kUP[&/Lc
int totalPage = 0; Pdf_{8r
sB0+21'R
if(totalRecords % everyPage == 0) cnLC> _hY
totalPage = totalRecords / everyPage; =#BeAsFfO
else rO]C`bg
totalPage = totalRecords / everyPage + 1 ; 1Dt"Rcn"4
X&wK<
return totalPage; 4bAgbx-^
} ,;/4E
NnHwk)'
privatestaticboolean hasPrePage(int currentPage){ V]q{N-Iq
return currentPage == 1 ? false : true; u:HKmP;
} Xid>8
Ub3,x~V
privatestaticboolean hasNextPage(int currentPage, W**=X\"'
.kC}. Q_
int totalPage){ <ya'L&
return currentPage == totalPage || totalPage == /@3+zpaw X
#H!~:Xu
0 ? false : true; J3:P/n&
} tH_#q"@)
IE_@:]K}Ja
v/m`rc]e
} v~jN,f*
IC}zgvcW
LrPDpTd
GC4$9q}C4Z
JYSw!!eC
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ;Ly4Z*!2
T{)!>)
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 rA1
gH6D
8OBvC\%
做法如下: 2$\f !6p
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 s|,]Nb=z/
ZM|>Va/X
的信息,和一个结果集List: b%oma{I=.c
java代码: etTuukq_Z
1c}'o*K_%
V>['~|
/*Created on 2005-6-13*/ qWanr7n]@
package com.adt.bo; Rw/G =zV@2
ED?s[K
import java.util.List; sm_:M| [D
U!e4_JBR'
import org.flyware.util.page.Page; I[4E?
y:,{U*49
/** R(zsn;
* @author Joa &1Y+q]
*/ \]9;c6(
publicclass Result { #5H@/o8!s=
EXBfzK)a
private Page page; vaQ,l6z
.h
M}nalr+#
private List content; ~f@<]
BMdr.0
/** #t/Q4X
+
* The default constructor bTiw?i+6Dv
*/ Y4{`?UM&h
public Result(){ VtKN{sSnu
super(); IK W!P1
} 0)P18n"$
C$tSsw?A
/** ':>B%k
* The constructor using fields hCDI;'ls
* YLCwo]\+>
* @param page a 6 ]!4
* @param content sW]n~kTt'
*/ N!m%~},s//
public Result(Page page, List content){ \O0fo^+U,,
this.page = page; r[,KE.^6~#
this.content = content; @"~\[z5
} G`
8j ^H,
r]E$uq
bR
/** c3}}cFe
* @return Returns the content. w1}[lq@
*/ )R|7> 97
publicList getContent(){ a>kDG <.A
return content; i]YQq! B
} n -=\n6"P
$bo^UYZ6
/** ^s?wnEo;j
* @return Returns the page. O[`Ob6Q{F
*/ l~=iUZW<
public Page getPage(){ :rj78_e9
return page; 7'8O*EoB'
} -m@s
9k
1]<!Xuk^f
/** 9F-k:hD |
* @param content W+eN%w5
* The content to set. ms{R|vU%b
*/ oF>GWstTR
public void setContent(List content){ E??%)q
this.content = content; FjydEV
} #<~f~{x
6,7omYof
/** [x)e6p)
* @param page OMZT\$9yT
* The page to set. 4tC_W!?$t
*/ g}D$`Nx:
publicvoid setPage(Page page){ K@i*Nl
this.page = page; 0l##M06>
} 7^iAc6QSy3
} *Q>:|F[vM
j*zK"n
M'HOw)U
j"V$J8)[
t#q>U%!
2. 编写业务逻辑接口,并实现它(UserManager, Ocb2XEF
"h2Ny#
UserManagerImpl) |]q=D1/A
java代码: s6D-?G*u%8
H94.E|Q\+
p3S c4
/*Created on 2005-7-15*/ [s/@z*,M1
package com.adt.service; Z])_E6.
n,F00YR
import net.sf.hibernate.HibernateException; Chua>p!$g
O)Qz$
import org.flyware.util.page.Page; @(
t:E`8
z(WpOD
import com.adt.bo.Result; H6I #Xj
"uCQm '
/** lkm(3y@']A
* @author Joa A!D:Kc3
*/ .}E)7"Qi,
publicinterface UserManager { lP
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j+9
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public Result listUser(Page page)throws 64lEB>VNm
V\ "5<>+O
HibernateException; [!le 9aNg
jE#8&P~
} CwvNxH#LVu
/RM-+D:Y
k)s 7Ev*
78)^vvn5~
k~#|8eLv
java代码: Q8x{V_Pot
a%!XLyq
^{s0d+@{
/*Created on 2005-7-15*/ ~Z2eQx
jtM
package com.adt.service.impl; l:eN u}{&
C6w{"[Wv=X
import java.util.List; f
99PwE(=
<<6w9wNon
import net.sf.hibernate.HibernateException; G!8pF
?nW#qy!R
import org.flyware.util.page.Page; b0X[x{k"
import org.flyware.util.page.PageUtil; 5B 7*Z
1%"`
=$q%
import com.adt.bo.Result; p]&Q`oh
import com.adt.dao.UserDAO; L_mqC(vn
import com.adt.exception.ObjectNotFoundException; [QbXj0en$
import com.adt.service.UserManager; .Qt3!ek
gN(hv.nQ
/** <gLtX[v!CL
* @author Joa l;A_Aii(
*/ YZRB4T9
publicclass UserManagerImpl implements UserManager { wF8\
j\f$r,4
private UserDAO userDAO; )|R9mW=k9P
~C/KA6H
/** od1omYsR
* @param userDAO The userDAO to set. 1`lFF_stkP
*/ UwkX[u
publicvoid setUserDAO(UserDAO userDAO){ ^4pKsO3ul
this.userDAO = userDAO; o2 d~
} suFOc
#@^w>D6W
/* (non-Javadoc) gF6j6
* @see com.adt.service.UserManager#listUser j7#GqVS'
i@5%d!J
(org.flyware.util.page.Page) /\cu!yiX
*/ oh~
vo!
public Result listUser(Page page)throws [IFRwQ^%_O
;Ia1L{472m
HibernateException, ObjectNotFoundException { HFuaoS+b*
int totalRecords = userDAO.getUserCount(); MuV0;K\
if(totalRecords == 0) WG
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throw new ObjectNotFoundException rs Uw(K^
@z)tC@
("userNotExist"); ""3m!qn#
page = PageUtil.createPage(page, totalRecords); ^YJA\d@
List users = userDAO.getUserByPage(page); PbUcbb17
returnnew Result(page, users); :ZS8Zm"
} +esNwz_
6^O?p2xpo
} Ln2C#Uf
t *
vg]Yc
Nu/Qa:H_{
|8 2tw|<o
>B /&V|E
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 jne9=Als5
IXvz&4VD
询,接下来编写UserDAO的代码: |4.o$*0Y
3. UserDAO 和 UserDAOImpl: gkML .u
java代码: ](>7h_2B
Xm:=jQn
QYfAf3te
/*Created on 2005-7-15*/ ~}-p5 q2
package com.adt.dao; uuYH6bw*d
#r.` V!=
import java.util.List; #oJbrh9J6
yF5
import org.flyware.util.page.Page; xPMyG);
_:X|R#d
import net.sf.hibernate.HibernateException; * \o$-6<
N~;
khS]
/** )^f9[5ee
* @author Joa %}MA5 t]o
*/ ;%7XU~<a
publicinterface UserDAO extends BaseDAO { QHs:=i~VH
&1E~ \8U
publicList getUserByName(String name)throws E)Qh]:<2v
s i"`
HibernateException; ]Uu(OI<)
.\~P -{Hd
publicint getUserCount()throws HibernateException; w$lfR,
4nII/cPG
publicList getUserByPage(Page page)throws z[\W\g*|ri
FW)^O%2s
HibernateException; 8jjk?PUD8
'!^E92
} N _~KZQ11^
sb|3|J6=
Q;XHHk
K>R;~
o
m-'(27
java代码: R8[iXXjku
#i +P(xV
Qw<kX*fxrI
/*Created on 2005-7-15*/ ECS<l*i57&
package com.adt.dao.impl; ,/?%y\:J
"T{~,'T
import java.util.List; adO!Gs9f?
I,<>%Z|'
import org.flyware.util.page.Page; Ukx/jNyYv
Ztyv@z'/Z
import net.sf.hibernate.HibernateException; qBBYckS.
import net.sf.hibernate.Query; I#S~
!q-:rW?c
import com.adt.dao.UserDAO; 762o~vY6$
-?aw^du
/** "zedbJ0
* @author Joa k>:/D
*/ nI*(a:
public class UserDAOImpl extends BaseDAOHibernateImpl t ?9;cS4
i_0,BVC
implements UserDAO { %on9C`/
9xK4!~5V
/* (non-Javadoc) qX
p,d
* @see com.adt.dao.UserDAO#getUserByName 1akD]Z
YMj7
(java.lang.String) )&Kn(l)
*/ +e0dV_T_>
publicList getUserByName(String name)throws T Oco({/_/
fXu~69_
HibernateException { P 34LV+e
String querySentence = "FROM user in class xxLgC;>[
_b!;(~@p
com.adt.po.User WHERE user.name=:name"; CRc!|?
Query query = getSession().createQuery xH"W}-#[
?GUz?'d
(querySentence); Ez/\bE
query.setParameter("name", name); N&I8nZ9
return query.list(); S2'`|uI
} 6+Wr6'kuH
.*EOVo9S
/* (non-Javadoc) R0Ax$Cv{
* @see com.adt.dao.UserDAO#getUserCount() vbRrk($`
*/ x2j/8]'o
publicint getUserCount()throws HibernateException { 28T\@zi
int count = 0;
NVO9XK
String querySentence = "SELECT count(*) FROM %A)-m 69
oh7#cFZZ0
user in class com.adt.po.User"; nr<WO~Xw~
Query query = getSession().createQuery hl6,#2$
Y7*(_P3/
(querySentence); 6(N.T+;]
count = ((Integer)query.iterate().next Gd30Be2gd
?418*tXd
()).intValue(); C.yY8?|
return count; 9UeVvH
} "pSH!0Ap\
r@*=|0(OrK
/* (non-Javadoc) 9N~8s6Ob
* @see com.adt.dao.UserDAO#getUserByPage $6:XsrV\a
wJ80};!
(org.flyware.util.page.Page) v Q-ixh
*/ 93Mdp9v+i
publicList getUserByPage(Page page)throws ^%n124
=bs.2aN&^
HibernateException { {B FT
String querySentence = "FROM user in class F5N>Uqr*oN
[{S;%Jj*X/
com.adt.po.User"; ?%cn'=>ZI
Query query = getSession().createQuery -yX.Jv
jIAW-hc]
(querySentence); -`zG_]=-
query.setFirstResult(page.getBeginIndex()) 0Jm]f/iZ
.setMaxResults(page.getEveryPage()); Tjnt(5 g
return query.list(); hAV2F#
} YPF&U4CN
Bii6Z@kS
} sg3h i"Im
N<KKY"?I'
{PN:bb
=4frP*H?
OJMvn'y
至此,一个完整的分页程序完成。前台的只需要调用 !Oeq
G
La`h$=#`
userManager.listUser(page)即可得到一个Page对象和结果集对象 wzD\8_;6N
JQ*D
的综合体,而传入的参数page对象则可以由前台传入,如果用 GN\8![J
E4Y"X
webwork,甚至可以直接在配置文件中指定。 -'80>[}q/
7<h.KZPc
下面给出一个webwork调用示例: ixOEdQ
java代码:
Y3-]+y%l
q{a#HnZo"
84iJ[Fq{
/*Created on 2005-6-17*/ Z:I*y7V-
package com.adt.action.user; }Q/G
&F
^F>4~68d
import java.util.List; ^Vag1(hdq
9aT L22U?
import org.apache.commons.logging.Log; %lXbCE:[
import org.apache.commons.logging.LogFactory; 7<^'DOs
import org.flyware.util.page.Page; n`P`yb\f$
T1l&B
import com.adt.bo.Result; ?V#Gx>\
import com.adt.service.UserService; &(gm4bTg
import com.opensymphony.xwork.Action; vGXWwQ.1Tp
g93I+
/** O[; +i
* @author Joa pPoH5CzcK
*/ S*4f%!
publicclass ListUser implementsAction{ <e'P%tG'
fk+1# 7{
privatestaticfinal Log logger = LogFactory.getLog s>T`l
fCLcU@3W?
(ListUser.class); Gu2_dT
.FuA;:@%\
private UserService userService; O4T'o.
smV!y8&
private Page page; Was'A+GZ
hQJo~'W=
privateList users; [u[ U_g*
(G#}*
/* /4yOs@#
* (non-Javadoc) 0[.3Es:_
* 8GY.){d!l
* @see com.opensymphony.xwork.Action#execute() e{5,'(1]
*/ 7krh4
publicString execute()throwsException{ EY]a6@;
Result result = userService.listUser(page); :JR<SFjm
page = result.getPage(); Lj4&_b9
users = result.getContent(); u2 7S%2P
return SUCCESS; Z+0?yQ=%
} jM*AL
X
|Td_S|:d
/** n<E.Em1
* @return Returns the page.
pL~=Z?(B
*/ ^b=XV&{q
public Page getPage(){ sD2
^_w6j
return page; (s088O
} [G\o+D?2
l1}R2lSEO
/** D%A@lMru
* @return Returns the users. ^+M><jE9
*/ aRX
publicList getUsers(){ 82|q7*M*.
return users; zwnw'
} Oo
kxg *!5
i-,'.w
/** p zg&/m&F`
* @param page or7pJy%4"
* The page to set. _e_4Q)z-a
*/ x:qr \Rz
publicvoid setPage(Page page){ H-Pq!9[DB
this.page = page; AQe!Sqg'
} lj*8mS/;h
l]$40 j
/** }%+qP+O\
* @param users Y[?`\c|
* The users to set. LP ,9<&"<
*/ Mm.Ql
publicvoid setUsers(List users){ %]#VdS|N
this.users = users; AeaPK
} k Q~ %=pn
|#V(p^
/** ge$LIsE8
* @param userService \dTQQ
* The userService to set. ".E5t@ }?m
*/ {S*!B
publicvoid setUserService(UserService userService){ 6Hwxx5>r
this.userService = userService; D
M}s0O$0
} "7d.i(vw
} a1|c2kT
.uKx>YB}
EI\v
g#qNHR
P_}/#N{C
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, [fxuUmU
q3)wr%!k5D
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ]H+{eJB7O
r4?b0&Xq
么只需要: 5>P7]?U.]
java代码: wyzOcx>M
|!Fk2Je,
&n|*uLn
<?xml version="1.0"?> -;>#3O-
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork (zC
/l6\^Xf{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- H|`R4hAk
&bLC(e]
1.0.dtd"> 74_xR
GRIa8>
<xwork> uY;R8CiD
Fu%X
<package name="user" extends="webwork- :+:6_x
On&L#pf
interceptors"> q@kOTkHv)
SdxY>;
<!-- The default interceptor stack name l{5O5%\,
4\6:\
--> q^*6C[G B
<default-interceptor-ref > :Ze4}(
i3PKqlp.
name="myDefaultWebStack"/> 2tf6GX:
VFSz-<L
<action name="listUser" Sl>>SP
6/6Rah!
class="com.adt.action.user.ListUser"> 8;#AO8+U7)
<param _]=9#Fg7{
P'tMu6+)
name="page.everyPage">10</param> JUQg 'D
<result 94{)"w]
XV=S)
name="success">/user/user_list.jsp</result> FVgMmYU
</action> +9[SVw8
<GF @L
</package> #*2Rp8n
~;unpym'
</xwork> 62kb2C
w^{!U
=IHje;s
7tgFDLA
O-PdM`mqW
[bjN
f2
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 :#$F)]y'\
J#aVo&.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。 <MdGe1n
V"#Jk!k9k
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Au5rR>W
6peyh_
2\0Oji\6
(A{NF(
O?ktWHUx
我写的一个用于分页的类,用了泛型了,hoho =& -[TPW
OOB^gf}$'
java代码: zZ=$O-&%
YH\j@^n
|pW\Ec#(
package com.intokr.util; {Q~7M$
Hm9<