Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6U ! P8q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3UUdJh<~
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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 (Y)2[j
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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 nnj<k5
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。 (-WRZLOQ
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分页支持类: **h4M2'C
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java代码: a|z-EKV
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package com.javaeye.common.util; m*]`/:/X[
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import java.util.List; 6HK1?
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publicclass PaginationSupport { G"?7 Z&+
*,Bm:F<m
publicfinalstaticint PAGESIZE = 30; rByth,|
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privateint pageSize = PAGESIZE; qhY+<S9
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privateList items; L4Jm8sy{
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privateint totalCount; 1 .+O2qB
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privateint[] indexes = newint[0]; SvSO?H!-
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privateint startIndex = 0; by>%}#M
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public PaginationSupport(List items, int X "7CN Td
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totalCount){ #4m5I="
setPageSize(PAGESIZE); eV*QUjS~
setTotalCount(totalCount); CBd%}il
setItems(items); 68z#9}
setStartIndex(0); zU!{_Ao9
} Vx<{cHQQ
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public PaginationSupport(List items, int "]=OR>
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totalCount, int startIndex){ 29J|eBvxx
setPageSize(PAGESIZE); nZB~l=
setTotalCount(totalCount); fsjLD|?|:
setItems(items); t[q2W"#.
setStartIndex(startIndex); $Xwk8<
} m[=SCH-;
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public PaginationSupport(List items, int ,Sgo_bC/|
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totalCount, int pageSize, int startIndex){ }SWfP5D@
setPageSize(pageSize); HjK8y@j
setTotalCount(totalCount); YWn""8p;P
setItems(items); y0p=E^QM
setStartIndex(startIndex); .eIs$
} :? B4q#]N
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publicList getItems(){ 9mHCms
return items; 7kV$O(4
} q*lk9{>
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publicvoid setItems(List items){ z+.G>0M
this.items = items; PFpFqJ)Cs"
} q}Po)IUT`5
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publicint getPageSize(){ \{<ml n
return pageSize; &PPnI(s^K
} 9)+!*(D
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publicvoid setPageSize(int pageSize){ FMCA~N
this.pageSize = pageSize; 8*8Y\"
} vVtkB$]L
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publicint getTotalCount(){ Ijiw`\;
return totalCount; B>E4,"
} ;s,1/ kA
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publicvoid setTotalCount(int totalCount){ =55)|$hgD
if(totalCount > 0){ NUnwf
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this.totalCount = totalCount; W\B@0Is o
int count = totalCount / 0*]0#2Z
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pageSize; A?HDY_u
if(totalCount % pageSize > 0) a?Fz&BE
count++; &O+S[~
indexes = newint[count]; -U>)B
for(int i = 0; i < count; i++){ ^'N!k{x
indexes = pageSize * Kc]
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i; A\ mSS
} @&HLm^j2O
}else{ IH*G7;
this.totalCount = 0; U{EcV%C2
} b6e2a/x
} 1 h(n}u
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publicint[] getIndexes(){ 3J4OkwqD
return indexes; hT=E~|O
} lnl>!z
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publicvoid setIndexes(int[] indexes){ Yc[vH=gV}
this.indexes = indexes; y1Br4K5C
} BThrv$D}
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publicint getStartIndex(){ 'U@Ep
return startIndex; p&XuNk
} uG.`
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publicvoid setStartIndex(int startIndex){ G?s;L NR
if(totalCount <= 0) !=vsY]
this.startIndex = 0; F+zHgE
elseif(startIndex >= totalCount) h/aG."U
this.startIndex = indexes L eUp!
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[indexes.length - 1]; vO zUAi
elseif(startIndex < 0) sN[<{;K4
this.startIndex = 0; xjDaA U,
else{ 7'.6/U
this.startIndex = indexes v{SYz<(
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[startIndex / pageSize]; 0rDQJCm
} X=Y>9
} @MH/efW.
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publicint getNextIndex(){ >|So`C3:e
int nextIndex = getStartIndex() + 2*1s(Jro
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pageSize; &O.S ;b*+
if(nextIndex >= totalCount) sGD b<
return getStartIndex(); .J3Dk=/
else oXkxd3
return nextIndex; ~8G<Nw4*\
} Wc)f:]7
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publicint getPreviousIndex(){ j/xL+Y(=
int previousIndex = getStartIndex() - e
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pageSize; eqze7EY
if(previousIndex < 0) pB;p\9A*q
return0; T9+ ?A
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else 3q.O^`y FU
return previousIndex; nP >*0Fq
} bh1WD_
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} 6"W~%FSJX
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抽象业务类 l&4TfzkY
java代码: 0iX;%SPYz
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/** j9za)G-J
* Created on 2005-7-12 l*]*.?m/5
*/ ccJ@jpXI
package com.javaeye.common.business; RYaf{i`
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import java.io.Serializable; %Y` @>P'
import java.util.List; & ;+u.X
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import org.hibernate.Criteria; 'Z+~G
import org.hibernate.HibernateException; y.~y*c6,g
import org.hibernate.Session; ]cnLJ^2
import org.hibernate.criterion.DetachedCriteria; z1ltc{~Z
import org.hibernate.criterion.Projections; lV-7bZ
import {@9y%lmrh
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org.springframework.orm.hibernate3.HibernateCallback; I#kK! m1Q
import V,($I'&/
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org.springframework.orm.hibernate3.support.HibernateDaoS 9LGJ -gL
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upport; PqIGc
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import com.javaeye.common.util.PaginationSupport; tqIz$84G
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public abstract class AbstractManager extends n< [np;\
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HibernateDaoSupport { \CL |=8[2
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privateboolean cacheQueries = false; T"'"T]^
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privateString queryCacheRegion; c/I.`@
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publicvoid setCacheQueries(boolean 50(/LV1
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cacheQueries){ :*e0Z2=
this.cacheQueries = cacheQueries; ]?xF'3#
} viAvD6e
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publicvoid setQueryCacheRegion(String &3>ki0L
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queryCacheRegion){ =eSG7QfS
this.queryCacheRegion = Va06(Cq
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queryCacheRegion; tq?lF$mM:
} BSG_),AH
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publicvoid save(finalObject entity){ n6[bF"v
getHibernateTemplate().save(entity); r^&{0c&o
} rSB"0W7
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publicvoid persist(finalObject entity){ 8UoMOeI3
getHibernateTemplate().save(entity); cn=~}T@~Z
} __$IbF5
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publicvoid update(finalObject entity){ &TSt/b/+W
getHibernateTemplate().update(entity); \i "I1xU
} R5G~A{w0
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publicvoid delete(finalObject entity){ bmc1S
getHibernateTemplate().delete(entity); ;'dw`)~jQ
} X(1nAeQ
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publicObject load(finalClass entity, 9'Y~! vY
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finalSerializable id){ SZ~Ti|^
return getHibernateTemplate().load LDW":k|
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(entity, id); ()K%Rn
} =lS~2C
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publicObject get(finalClass entity, FJv=5L
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finalSerializable id){ $.cNY+ k
return getHibernateTemplate().get 6
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(entity, id); Et%s,zeA{2
} /+P
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publicList findAll(finalClass entity){ *(s+u~, I
return getHibernateTemplate().find("from Q<d\K(<3?:
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" + entity.getName()); ,|"tLN*m
} 4CS9vv)9R
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publicList findByNamedQuery(finalString KB7CO:
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namedQuery){ 2<yi8O\
return getHibernateTemplate _C&2-tnp
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().findByNamedQuery(namedQuery); I_'S|L
} }-)2CEj3L%
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publicList findByNamedQuery(finalString query, A"\kdxC
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finalObject parameter){ Vur$t^zE
return getHibernateTemplate ,`G8U/
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().findByNamedQuery(query, parameter); $91c9z;f^
} D.j'n-yw
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publicList findByNamedQuery(finalString query, ~o= Sxaf
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finalObject[] parameters){ m7^aa@^m
return getHibernateTemplate z;GnQfYG
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().findByNamedQuery(query, parameters); &iR>:=ksN
} 6/wAvPB$
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publicList find(finalString query){ A0cC)bd&
return getHibernateTemplate().find X +*@
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(query); za1MSR
} vO%n~l=
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publicList find(finalString query, finalObject x$J1%K*
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parameter){ 0V"r$7(}
return getHibernateTemplate().find >1,.4)k%K
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(query, parameter); h$DFp
} m7zen530
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public PaginationSupport findPageByCriteria GX&BUP\
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(final DetachedCriteria detachedCriteria){ n%"q>
return findPageByCriteria >:Na^ +c
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); efy65+~GG
} >zFe)
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public PaginationSupport findPageByCriteria 7u6o~(
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(final DetachedCriteria detachedCriteria, finalint "2i{ L '
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startIndex){ .|JJyjRA+
return findPageByCriteria v98=#k!F
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(detachedCriteria, PaginationSupport.PAGESIZE, }\:3}'S.$
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startIndex); 1Zx|SBF
} aA-A>z
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public PaginationSupport findPageByCriteria u01 'f-h
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(final DetachedCriteria detachedCriteria, finalint L$cNxz0$
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pageSize, Jor>YB`X
finalint startIndex){ -GD_xk
return(PaginationSupport) "yCCei,hA?
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getHibernateTemplate().execute(new HibernateCallback(){ K19/M1~
publicObject doInHibernate "fdgBso
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(Session session)throws HibernateException { --d<s
Criteria criteria = ;gYW!rM
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detachedCriteria.getExecutableCriteria(session); F^7qLvh
int totalCount = K~H)XJFF
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((Integer) criteria.setProjection(Projections.rowCount (wEaa'XL
L@HPU;<
()).uniqueResult()).intValue(); l_hM,]T0
criteria.setProjection P,k~! F^L
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(null); 8*!<,k="9
List items = mTz %;+|L
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criteria.setFirstResult(startIndex).setMaxResults "^F#oo%L
:6S!1roi
(pageSize).list(); 1 !bODd
PaginationSupport ps = Y ( x_bJ
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new PaginationSupport(items, totalCount, pageSize, .+MJ' bW
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startIndex); jl;_lcO
return ps; `uM:>
} &PaqqU.
}, true); dF:@BEo
} QO0}-wZR
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public List findAllByCriteria(final k__i Jsk
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DetachedCriteria detachedCriteria){ Zk4Hs%n
return(List) getHibernateTemplate GR@!mf
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().execute(new HibernateCallback(){ X,n4_=f
publicObject doInHibernate &lbxmUeU
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(Session session)throws HibernateException { Ni#!C:q
Criteria criteria = {e\Pd!D?|
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detachedCriteria.getExecutableCriteria(session); /ts=DxCC;
return criteria.list(); .<`i!Ls
} ig<Eyr
}, true); [zl@7X1{_
} _8P"/(
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public int getCountByCriteria(final _x&;Fa%
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DetachedCriteria detachedCriteria){ <f.* =/]W2
Integer count = (Integer) gF-<%<RV
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getHibernateTemplate().execute(new HibernateCallback(){ h6<abT@I
publicObject doInHibernate ~T@t7Cg
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(Session session)throws HibernateException { x|U~?
Criteria criteria = 7 4Xk^8
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detachedCriteria.getExecutableCriteria(session); KY34Sc
return ?j;e/r.
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criteria.setProjection(Projections.rowCount &IsQgS7R
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()).uniqueResult(); nwswy]e8/
} +^ a9i5
}, true); bP\0S@1YL
return count.intValue(); A'r 3%mC
} E9z^# @s
} qzS 9ls>>
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用户在web层构造查询条件detachedCriteria,和可选的 o|Cq#JFG
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 /WlK*8C
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PaginationSupport的实例ps。 6hDK;J J&
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ps.getItems()得到已分页好的结果集 i{[=N9U5o
ps.getIndexes()得到分页索引的数组 y_EkW
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ps.getTotalCount()得到总结果数 uw!
ps.getStartIndex()当前分页索引 JwCv(1$GM
ps.getNextIndex()下一页索引 u$ [R>l9
ps.getPreviousIndex()上一页索引 +13h*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8|^dM$
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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 6BM[RL?T
9ZvBsG)
一下代码重构了。 fm$eJu
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我把原本我的做法也提供出来供大家讨论吧: ?CO\jW_
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首先,为了实现分页查询,我封装了一个Page类: r_C|gfIP
java代码: 0\v98g<[+
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/*Created on 2005-4-14*/ F*V<L
package org.flyware.util.page; <!b~7sZkTc
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/** ' =MaO@ @
* @author Joa fxfzi{}uj
* r@C2zF7
*/ P^m+SAAB
publicclass Page { z'@j9vT
n8<o*f&&9>
/** imply if the page has previous page */ dFY]~_P472
privateboolean hasPrePage; n\d`Fk
i`[5%6\"&
/** imply if the page has next page */ [MSLVTR
privateboolean hasNextPage; 9$,x^Qx
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/** the number of every page */ h(}$-' g
privateint everyPage; |GuIp8~
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/** the total page number */ &8'.Gwm}
privateint totalPage; vZV+24YWb
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/** the number of current page */ D|8vS8p
privateint currentPage; m-f"EFmP
A
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/** the begin index of the records by the current _&S?uz m
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query */ iku8T*&uc
privateint beginIndex; _XT],"
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/** The default constructor */ kPwgayz
public Page(){ :}d`$2Dz
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} .qVz rS
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/** construct the page by everyPage p.KX[I
* @param everyPage 9hAS#|vK
* */ mv@cGdxu
public Page(int everyPage){ dz/'
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this.everyPage = everyPage; @|Z:7n6S
} :xw2\:5~0
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/** The whole constructor */ "|W .o=R
public Page(boolean hasPrePage, boolean hasNextPage, O+;0|4V%
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int everyPage, int totalPage, b i^h&H
int currentPage, int beginIndex){ _`lj
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this.hasPrePage = hasPrePage; u2HkAPhD
this.hasNextPage = hasNextPage; pAS!;t=n,
this.everyPage = everyPage; rQiX7
this.totalPage = totalPage; EubR]ckB
this.currentPage = currentPage; htc& !m
this.beginIndex = beginIndex; $ q*kD#;mh
} -1Y9-nn[m
gyH'92ck
/** /x.TF'Z*
* @return Q,Tet&in )
* Returns the beginIndex. ]2G5ng' @
*/ 6cof Zc$
publicint getBeginIndex(){ >}QRMn|@H
return beginIndex; w?CbATQ
} 0P`wh=")
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/** ^_4TDC~h
* @param beginIndex '^ '4C'J
* The beginIndex to set. 1@IRx{v$
*/ j`^':!
publicvoid setBeginIndex(int beginIndex){ 9@AGx<S1
this.beginIndex = beginIndex; Mr'}IX5
} XfA3Ez,}
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/** 3_=~7B)
8
* @return
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* Returns the currentPage. $,08y
*/ n+@}8;oeP
publicint getCurrentPage(){ Mq) n=M
return currentPage; JV'd!5P
} 8>x.zO_.c>
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/** \3K 6NA!L
* @param currentPage m%V+px
* The currentPage to set. zjgK78!<
*/ J#Fe"
publicvoid setCurrentPage(int currentPage){ Sp)KtMV
this.currentPage = currentPage; m}.ru)^p
} A/N*Nc
':#?YQ}2
/** j)\g0u6
* @return TRz~rW
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* Returns the everyPage. :NU-C!eT
*/
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publicint getEveryPage(){ rh2pVDS
return everyPage; IWu^a w
} i]GBu
hM
E|=\
/** R7*Jb-;$!
* @param everyPage Wq)'0U;{$
* The everyPage to set. A{h
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*/ qGkrG38K
publicvoid setEveryPage(int everyPage){ ~C5iyXR
this.everyPage = everyPage; !mBsDn(J
} X[k-J\
A(_AOoA'
/** B%6bk.
* @return L5T)_iQ5
* Returns the hasNextPage. Bir}X
*/ oSNB\G<
publicboolean getHasNextPage(){ 80$P35Q"
return hasNextPage; ]Oc
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} Af=%5%
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/** .Q"3[
* @param hasNextPage f[7'kv5S
* The hasNextPage to set. t^?8Di\
*/ <Hp"ZCN
publicvoid setHasNextPage(boolean hasNextPage){ 4A&e+kz&:R
this.hasNextPage = hasNextPage; WY,t> 1c
} @v'D9 ?
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/** h<M7[p=
* @return 98]t"ny [
* Returns the hasPrePage. 0
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*/ HB}gn2.1&
publicboolean getHasPrePage(){ Gh
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return hasPrePage; A)#sh)
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} !$?@;}=
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i
/** YfalsQ8
* @param hasPrePage q!TbM"
* The hasPrePage to set. =4D_-Q
*/ $P-m6
publicvoid setHasPrePage(boolean hasPrePage){ +,[3a%c)H
this.hasPrePage = hasPrePage; I5A^/=bf&
} </Id';|v
n96gDH*
/** Fs|;>Up0
* @return Returns the totalPage. YUb,5Y0
* L,Nr,QC-
*/ z|<oxF.
publicint getTotalPage(){ ^;3rdBprm
return totalPage; CJOl|"UyJ
} ]aRD6F:L
`|w#K28t"
/** +m.8*^
* @param totalPage ) T1oDk
* The totalPage to set. *N r|G61
*/ >FHsZKJ
publicvoid setTotalPage(int totalPage){ -IS9uaT5
this.totalPage = totalPage; /RC!Yi
} de6dLT>m
nnNg^<[k3
} Bg
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Z
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个PageUtil,负责对Page对象进行构造: %`1vIr(7
java代码: =)YYx8gR
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/*Created on 2005-4-14*/ SU'9+=_$
package org.flyware.util.page; xUpb1R
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import org.apache.commons.logging.Log; /&d`c=nH
import org.apache.commons.logging.LogFactory; sri#L+I
#6jwCEo=V
/** &] 6T^.
* @author Joa :"^<
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* /&:9VMMj
*/ .K1E1Z_
publicclass PageUtil { BDRVT Y(s
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privatestaticfinal Log logger = LogFactory.getLog t)Q@sKT6
@%nUfG7TQ
(PageUtil.class); xJLO\B+gM
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/** AdW2o|Uap
* Use the origin page to create a new page rOHW
* @param page TQd FC\@f"
* @param totalRecords Q|KD/s??
* @return VQ<i$ I
*/ ].P(/~FS9
publicstatic Page createPage(Page page, int }l?_Cfvu
U<Y'.!
totalRecords){ W7=_u+0d
return createPage(page.getEveryPage(), \y`3Lh Y
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page.getCurrentPage(), totalRecords);
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} /_OZ1jX
;T{/;
/** /)?P>!#;\
* the basic page utils not including exception K_|~3g
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handler :@`(}5F4
* @param everyPage w1#jVcUQ
* @param currentPage kr`BUW3
* @param totalRecords ';\gR/L
* @return page <GgtP55
*/ u?3NBc$~A
publicstatic Page createPage(int everyPage, int AJ`
v
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currentPage, int totalRecords){ '#i]SU&*
everyPage = getEveryPage(everyPage); AOx3QgC^NO
currentPage = getCurrentPage(currentPage); FT/5 _1i
int beginIndex = getBeginIndex(everyPage, o-=d|dWG
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currentPage); XVDd1#h
int totalPage = getTotalPage(everyPage, +%qSB9_>N{
QiE<[QP{g
totalRecords); rKQASRF5*
boolean hasNextPage = hasNextPage(currentPage, px}7If
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totalPage); hY=
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boolean hasPrePage = hasPrePage(currentPage); JM-ce8U
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returnnew Page(hasPrePage, hasNextPage, J&"?m.~@
everyPage, totalPage, LbX6p
currentPage, aMvK8C%7
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beginIndex); CxA\yG3L&
} 7vpN6YP
-j`!(IJ
privatestaticint getEveryPage(int everyPage){ Wbn[Q2h5
return everyPage == 0 ? 10 : everyPage; (OyY_`
} +8)]m<
8f,'p}@!d
privatestaticint getCurrentPage(int currentPage){ mo#0q&ZQ
return currentPage == 0 ? 1 : currentPage; HA9Nr.NqC@
} =tc`:!$
_:gGD8
privatestaticint getBeginIndex(int everyPage, int S
$_Y/x
$EQT"ZX>%i
currentPage){ /iTUex7T
return(currentPage - 1) * everyPage; > 1r[]&8
} YNg\"XjJM<
_(6B.
privatestaticint getTotalPage(int everyPage, int [+'BQ
.:Bwa
totalRecords){ S#h'\/S
int totalPage = 0; (~7m"?
Z<N&UFw7QJ
if(totalRecords % everyPage == 0) uZo`IK J
totalPage = totalRecords / everyPage; c{,y{2c]LT
else =X`]Ct8Z
totalPage = totalRecords / everyPage + 1 ; /NW>;J}C
&,N3uy;Gc
return totalPage; (~G5t(+
} :otY;n -
c}IX"
privatestaticboolean hasPrePage(int currentPage){ Ig02M_
return currentPage == 1 ? false : true; @L[PW@:SZ
} s!@=rq
/o|PA:6J
privatestaticboolean hasNextPage(int currentPage, :Hzz{'
(:?5 i`
int totalPage){ t +3
return currentPage == totalPage || totalPage == >[|GC/C
8O8\q
;US
0 ? false : true; d2C[wQF
} }fJ:wku
~KAp\!,
{d 1N&
} ]27>a"p59Y
FJa[ToZ4+
U]V3DDN
@V* ju
~aJW"\{
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。 YY#s=
-E8ntY-
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 !,? <zg
Uz6{>OCvk|
做法如下: c~gNH%1XN
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 'v\1:zi
&/>;LgN
的信息,和一个结果集List: 0" U5oP[
java代码: "UQr :/
),cQUB
(s}Rj)V[^
/*Created on 2005-6-13*/ aF&r/j+}o
package com.adt.bo; SON^CvMs{
;x:k-s2-
import java.util.List; 6R 1wn&8
ny12U;'s,
import org.flyware.util.page.Page; Sf
024
eJU;*] xfH
/** .'t (-eT,
* @author Joa Ku<b0<`
*/ gYTyH.
publicclass Result { 2{A;du%&
,|T*|2Gm
private Page page; M82.khm~jM
8hTR*e!+
private List content; <|{L[
pN\)(:"8v
/** 9W{,=.%MX$
* The default constructor CfPXn0I
*/ V";mWws+?#
public Result(){ K #qoR /:
super(); &`9j)3^J.
} e>L5.~i
z.eJEK
/** ]b4pI*:$I
* The constructor using fields Ik`O.Q.}
* o3Mf:;2c C
* @param page BZovtm3E
* @param content $Y8>_6%+T
*/ 99 <4t$KH
public Result(Page page, List content){ E%<w5d.lq
this.page = page; v<L=!-b^
this.content = content; nd.57@*M
} J.1O/Pw!.a
S5uJX#*;
/** H_VEPp,T
* @return Returns the content. rHvF%o
*/ _Zh2eXWdjM
publicList getContent(){ CQ@LmTW[
return content; $Mdbto~ <
} LtC~)R
R<"2%oY
/** %tT"`%(+
* @return Returns the page. Z;ZuS[ZA
*/ /_]ltX D
public Page getPage(){ hHcJN
return page; P+[QI
U
} TqIAWbb&
"gFxfWIA
/** s(Z(e %
* @param content YTQ5sFuGM
* The content to set. j]rXoV>
*/ /+>)"D6'
public void setContent(List content){ ZTN(irK
this.content = content; &|)hCJu
} $j57LY|r
js~tKUvg
/** F "!agc2!
* @param page \Ke8W,)ew
* The page to set. yH*hL0mO
*/ TYYp"wx
publicvoid setPage(Page page){ G 0hYFc u
this.page = page; @&;(D!_&
} Z+ixRch@-s
} v2d<o[[C
?-pi,O~(p
BWWq4mdb{
zG_p"Z7,
_}D%iJg#
2. 编写业务逻辑接口,并实现它(UserManager, KE<kj$
.Y;b)]@f
UserManagerImpl) aYqm0HCT
java代码: :pRF*^eU
+#4]o
}6G
tv0Ha A
/*Created on 2005-7-15*/ T=WNBqKo]
package com.adt.service; UH[<&v
hR-K@fS%l'
import net.sf.hibernate.HibernateException; aR _NyA
qP7G[%=v
import org.flyware.util.page.Page; WJfES2N
2UiR~P]%
import com.adt.bo.Result; GD!-
qH
e9&+vsRmA
/** 62Mdm3
* @author Joa </= CZy5w
*/ 5y]io
Jc9-
publicinterface UserManager { 6Opa{]
r088aUO
P
public Result listUser(Page page)throws ^5>s7SGB"
$_sYfU9
HibernateException; C}q>YRubZ
.jA\f:u#
} Z^+rQ.%n"&
qe?Qeh(!X
uMvb-8
g5i#YW
[]zua14F6
java代码: yG\UW&P
1]T|6N?
/%!~x[BeJ>
/*Created on 2005-7-15*/ e'34Pw!m
package com.adt.service.impl; Pe}PH
I
u^=`%)
import java.util.List; T?n-x?e
%t*[T
import net.sf.hibernate.HibernateException; ~h!
13!
GX
}q9
import org.flyware.util.page.Page; /4*W DiH
import org.flyware.util.page.PageUtil; #jBN?Z#
=s;M]:
import com.adt.bo.Result; 4J5pXlzV
import com.adt.dao.UserDAO; FbAW_Am(
import com.adt.exception.ObjectNotFoundException; !;v.>.lw
import com.adt.service.UserManager; OUI6
ax\[
g\Ak;03n
/** 9C/MRmv`
* @author Joa v>H=,.`0\
*/ D<bI2
publicclass UserManagerImpl implements UserManager { G(/DtY]
%?9Ok
private UserDAO userDAO; z\T Lsx
Lg4YED9#
/** /ylc*3e'4
* @param userDAO The userDAO to set. 9[VxskEh
*/ /1d<P! H
publicvoid setUserDAO(UserDAO userDAO){ "UG
K8x
this.userDAO = userDAO; &J$##B
} e"k/d<
OX\$ nQ\o
/* (non-Javadoc) W\8Ln>
* @see com.adt.service.UserManager#listUser Z(e^ iH
?qmp_2:WU
(org.flyware.util.page.Page) _'!kuE,*1
*/ e)@3m.
public Result listUser(Page page)throws k,@J&
QlS5B.h,
HibernateException, ObjectNotFoundException { 28)TXRr-
int totalRecords = userDAO.getUserCount(); (En\odbvt
if(totalRecords == 0) ~r!5d@f.6
throw new ObjectNotFoundException wr$}AX
g_>ZE
("userNotExist"); -oZac
page = PageUtil.createPage(page, totalRecords); `;_tt_
List users = userDAO.getUserByPage(page); f~q&.,I(
returnnew Result(page, users); #w*pWD^
} qbEj\
b[
O9|'8"AF
} epR~Rlw>2
)PG,K4z
C}h@ El
7XDV=PQ[
Gtg)%`
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Ky yG8;G%
I1myu Z
询,接下来编写UserDAO的代码: _M&.kha
3. UserDAO 和 UserDAOImpl: bg ,}J/
java代码: r9M={jC
h3kHI?jMWG
(v`;ym
/*Created on 2005-7-15*/ #8z,'~\
package com.adt.dao; w}Upa(dU
=_'cG:=)
import java.util.List; I:e2sE
":
AIm$in`P
import org.flyware.util.page.Page; jOb[h=B"
nP3GI:mjL
import net.sf.hibernate.HibernateException; |w JZU
Y/S3)o
/** 2*citB{
* @author Joa X?6h>%) k
*/ VU/W~gb4"A
publicinterface UserDAO extends BaseDAO { eCp| QSXE
>$mSFJz5S
publicList getUserByName(String name)throws Q@2tT&eL
_=L;`~=C9e
HibernateException; \u]CD}/
lkfFAwnc
publicint getUserCount()throws HibernateException; CJ?gjV6
m"G N^V7
publicList getUserByPage(Page page)throws "k-ov9yK
\B2d(=~4
HibernateException; '%EZoc/U
d# 3tQ*G/
} m IzBK]@^
%<?ciU
4*vas]
be:phS4vz
-L9R&r#_e
java代码: Ys$YI{
v1C.\fL
Tq84Fn!HJ>
/*Created on 2005-7-15*/ T'M66kg
package com.adt.dao.impl; Q==v!"Gi|
jAK{<7v4U
import java.util.List; VK'T[5e
b|dCEmFt
import org.flyware.util.page.Page; O4/n!HOb
&ZE\@Vc
import net.sf.hibernate.HibernateException; ;x-H$OZX
import net.sf.hibernate.Query; |2@en=EYk
jBv$^L
import com.adt.dao.UserDAO; 2 1~7{#
q{GSsDo-:V
/** p%"yBpSK
* @author Joa ^v!im\ r
*/ DvX3/z#T
public class UserDAOImpl extends BaseDAOHibernateImpl Iv(Qa6(
naIv=
implements UserDAO { }{8Fo4/
cH;TnuX
/* (non-Javadoc) D4q>R;
* @see com.adt.dao.UserDAO#getUserByName m`$>:B
V+qJrZ,i
(java.lang.String) g6g$nY@Jm
*/ hoR=%pC*
publicList getUserByName(String name)throws 3l%,D:
?
M{xVkXc>
HibernateException { ?{: D,{+
String querySentence = "FROM user in class HRV*x!|I
/u)Rppu
com.adt.po.User WHERE user.name=:name"; lKEX"KQ!
Query query = getSession().createQuery 0HR|aqPo
^5]uBOv
(querySentence); gKN}Of@^1
query.setParameter("name", name); L"foL
return query.list(); C4{\@v}t
} ISS\uj63M
s8_aL)@f
/* (non-Javadoc) :Sc8PLT
* @see com.adt.dao.UserDAO#getUserCount() zBt`L,^
*/ :,kU#eZ$-
publicint getUserCount()throws HibernateException { Vf0fT?/K
int count = 0; \ CK(;J
String querySentence = "SELECT count(*) FROM JA)o@[lF
"#twY|wW
user in class com.adt.po.User"; Cqgk
Query query = getSession().createQuery %f(S'<DhC
JzMZB"Z?
(querySentence); pDq#8*q+v
count = ((Integer)query.iterate().next #9`r XEz
(`6%og#8
()).intValue(); w(/DTQc~d
return count; -@2'I++"@
} A)Qh
Kej|1g1f
/* (non-Javadoc) Y}LLOj@L
* @see com.adt.dao.UserDAO#getUserByPage ~XUOW Y75
uxOJ3
(org.flyware.util.page.Page) EqnpMHF
*/ {pDTy7!Hs
publicList getUserByPage(Page page)throws UP;Q= t
ivzAlwP
HibernateException { v**z$5x9
String querySentence = "FROM user in class kG1;]1tT#
[q-;/ed
com.adt.po.User"; dTN$y\
Query query = getSession().createQuery *bA+]&dj\
u#+RUtM
(querySentence); 9g
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query.setFirstResult(page.getBeginIndex()) ?MC(}dF0
.setMaxResults(page.getEveryPage()); Xsd$*F@<
return query.list(); \+k, :8s/
} ^/>Wr'w
4\N_ G
@
} J/'M N
wE$s'e
5"JU?e59M
F7{R~mS;
c>ad0xce6
至此,一个完整的分页程序完成。前台的只需要调用 1")FWN_K/T
p9-0?(]
userManager.listUser(page)即可得到一个Page对象和结果集对象 M8';%=@
G#H9g PY
的综合体,而传入的参数page对象则可以由前台传入,如果用 bD35JG^&i
74K)aA
webwork,甚至可以直接在配置文件中指定。 X JY5@I.
^qxdmMp)l
下面给出一个webwork调用示例: A&?}w_|9
java代码: x;]x_fz
Ge~q3"
k-"<{V
/*Created on 2005-6-17*/ ^m*3&x8
package com.adt.action.user; E4+b-?PB~
$$JIBf8
import java.util.List; ll^DY
hx}
?6i;)eIOI
import org.apache.commons.logging.Log; 3AURzU
import org.apache.commons.logging.LogFactory; {6'*Phw
import org.flyware.util.page.Page; W`$[j0
<cYp~e%xIw
import com.adt.bo.Result; &hayR_F9
import com.adt.service.UserService; cd!|Ne>fe
import com.opensymphony.xwork.Action; .nEs:yn
Is13:
/** nv"G;W
* @author Joa p8=|5.
*/ Qyz>ZPu}sz
publicclass ListUser implementsAction{ u4YM^* S.
&Yp+k}XU
privatestaticfinal Log logger = LogFactory.getLog Xo Y7/&&
@,k7xm$u
(ListUser.class); s~^*+kq
td >,TW=A*
private UserService userService; .Gh%p`<
lop uf/U0
private Page page; B{p4G`$i1
ic-IN~J-
privateList users; iJ)0Y~
&<Mt=(qY1
/* '[nmFCG%m*
* (non-Javadoc) wcZbmJ:
* H"+wsM^@
* @see com.opensymphony.xwork.Action#execute() f&ytK
*/ Wr5 Q5s)c
publicString execute()throwsException{ 1}!L][(
Result result = userService.listUser(page); ,/&Z3e
page = result.getPage(); @`w n<%o$
users = result.getContent(); |5,<jyp
return SUCCESS; tMFsA`ng
} h4(JUio
.+yW%~0
/** j0FW8!!-g
* @return Returns the page. 3B{[%#vO
*/ ?,07;>&
public Page getPage(){ ]#zZWg
zv
return page; G2]^F Y
} /s|{by`we4
:y#T9R9
/** / p)F>WR
* @return Returns the users. #Qh>z%Mn^3
*/ dl0FQNz8@B
publicList getUsers(){ 0xCz'mJ
return users; q8xd*--#
} `T"rG}c
c@R; /m:R
/** \a))
* @param page uZIJoT
* The page to set. _BS
9GB
*/ 7,'kpyCj
publicvoid setPage(Page page){ ?NG=8.p
this.page = page; +=eR%|!@
} 51 b y
+Ok%e.\ZM
/** 6|!NLwa
* @param users {38\vX,I(w
* The users to set. Z\? E3j
*/ ;YyXT"6/p
publicvoid setUsers(List users){ rh%m;i<b
this.users = users; 3o6RbW0[
} |P~;C6sf
2f{T6=SK
/** i sW\MB]
* @param userService sJZ!sznn
* The userService to set. ZFvyL8o
*/ T_;]fPajjD
publicvoid setUserService(UserService userService){ dqc1q:k?$
this.userService = userService; gR Nv-^
} *:hyY!x
} mfom=-q3k
Dl C@fZD
".U^ifF
riCV&0"n
WE6\dhJ<
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, }Ln@R~[
~/-eyxLTm
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 -rSIBc:$8
{fDTSr?/
么只需要: +(?>-3_z
java代码: U \oy8FZ
kV&9`c+
aeP[+ I9
<?xml version="1.0"?> cpZc9;@IC
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork S%mfs!E>
Ug%_@t/?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Bv9kSu9'~
5[gh|I;D
1.0.dtd"> !EBY@ Y1
0Scm?l3
<xwork> \9{F5Sz
}|wv]U~
<package name="user" extends="webwork- Yu3zM79'k
9YN?
interceptors"> K#mOSY;}
\7v)iG|#G&
<!-- The default interceptor stack name QM<y`cZ8
.Y*f2A.v
--> },@^0UH4c
<default-interceptor-ref S*
R,FKg
7 sFz?`-
name="myDefaultWebStack"/> y$W|~ H
V@vU"
<action name="listUser" )3A{GZj#6
BiwieF4x
class="com.adt.action.user.ListUser"> !mJo'K
<param LnsD
Ao9R:|9
name="page.everyPage">10</param> DcD{*t?x
<result 1Sz A3c
:t("L-GPW
name="success">/user/user_list.jsp</result> l$xxrb9P!
</action> d_z59
3=0E!e
</package> K^l:MxO-X
Ms^dRe)
</xwork> mpw~hW0-
ZWUP^V
3gZ8.8q3
3_$w|ET
*OjKcs
An`3Ex[
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 IE2"rQ T
.)tSg
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。 XMIbUbUk-
f9u^ R=Ff[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 hT g<*
`#P$ ]:
S>Yj@L
S$q=;"
'tgKe!-@
我写的一个用于分页的类,用了泛型了,hoho hqvE!Of
Guw}=l--YR
java代码: )cJ#-M2
}_'IE1bA
W_|0y4QOo
package com.intokr.util; 0%Ll
fxcc<h4
import java.util.List; Jju#iwb
r=uN9ro
/** o{qr!*_3
* 用于分页的类<br> [Nm4sI11
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Sjj>#}U
* =8Jfgq9E
* @version 0.01 M~e0lg8
* @author cheng k%c{ETdE
*/ dUrElXbXd
public class Paginator<E> { ||7x;2e
privateint count = 0; // 总记录数 &)d$t'7p
privateint p = 1; // 页编号 y9H%
Xl
privateint num = 20; // 每页的记录数 <xpph
t<
privateList<E> results = null; // 结果 ZUm?*.g\^
\>. LW9
/** 1/+C5Bp*
* 结果总数 {$D,?V@%_
*/ /*FH:T<V
publicint getCount(){ CqMhk
return count; d[^KL;b?6
} z4%uN|V
ipnV$!z
publicvoid setCount(int count){ HAz By\M{
this.count = count; |077Sf|
} 3rW|kkn
'NjzgZ~]P
/** 7,qYV}
* 本结果所在的页码,从1开始 :$;Fhf<5
* }_/Hdmmx
* @return Returns the pageNo. q%n6K
*/ gN8hJG'0
publicint getP(){ $,=6[T!z+e
return p; SvM6iZ]
} S_MyoXV
jd]s<C3o
/** "xI"
* if(p<=0) p=1 aimarU
* qU2~fNY
* @param p k %e^kej
*/ {R<Ea
@LV+
publicvoid setP(int p){ >zsid:
if(p <= 0)
/-_=nf}w
p = 1; H`bSYjgM!
this.p = p; >WJf=F`_H
} xJ^>pg8
G@FI0\t
/** oBQ#eW aY
* 每页记录数量 fqX"Lus `=
*/ y.5/?{GL
publicint getNum(){ }VS3L_
;}/
return num; oF9
-&
} s4Sd>D7
KH)D08
/** oVA?J%EK
* if(num<1) num=1 N7'OPTKt&
*/ Ds#/
publicvoid setNum(int num){ kIw`P[
if(num < 1) )[H{yQ
num = 1; !-2R;yo12
this.num = num; 'j^xbikr
} ]V %.I_
D0k
8^
/** e0@6Pd
* 获得总页数 n55Pv3}C
*/ v(*C%.M)
publicint getPageNum(){ 9CA^B2u
return(count - 1) / num + 1; f.aSKQD
} q{s(.Uq$&
I}e3zf>
/** 0&qr
* 获得本页的开始编号,为 (p-1)*num+1 9TF f8'?d
*/ ~<<nz9}o_
publicint getStart(){ EXP%Mk/
return(p - 1) * num + 1; .)}@J5P)
} R>DaOH2K*
ZX ?yL>4
/** }X x(^Zh
* @return Returns the results. Um1[sMc{au
*/ Z3>N<u8)
publicList<E> getResults(){ a#mNE*Dg
return results; X37 L\e[c
} ,yd
MU\so(
]| N3eu
public void setResults(List<E> results){ ^~{$wVGa
this.results = results; a+hd(JX0~
} o]nw0q?
`cPywn@uGZ
public String toString(){ rl9.]~
StringBuilder buff = new StringBuilder ?$f)&O
uwRr LF
(); fLV"T_rk
buff.append("{"); %6AW7q
t
buff.append("count:").append(count); KD/V aN
buff.append(",p:").append(p); pF
^#}L
buff.append(",nump:").append(num); O+%WR
buff.append(",results:").append |
8qBm
:2njp%
(results); 2X:4CC%5
buff.append("}"); z4&iK)x
return buff.toString(); V9ssH87#
} LL|7rS|o
,J`'Y+7W
} nW;g28
aM7uBx\8 5
sp@E8G%xO