我们巨匠都知道,在措置多线程处事并发时,因为建树线程需要占用良多的系统资本,所觉得了避免这些不需要的损耗,凡是我们采用线程池来解决这些问题。
3 V( A1 F/ M c/ E5 M1 X; \& y 线程池的根基事理是,首先建树并连结必然数目的线程,当需要使用线程时,我们年夜池中取得线程,再将需要运行的使命交给线程进行措置,当使命完成后再将扑晔着回池中。9 V5 R, |" Y# x: O9 W
下面,我给出一个很简单的实现模子,仅供参考。
. [- [" f$ Y' j, N+ u, D ThreadPool.java/ s. C* M% O2 Q, j9 N
package org.loon.framework.util.test;
$ j$ e# d+ |9 m: n7 c1 C import java.util.LinkedList;- i x) A. B% q' Z4 X
import java.util.List;+ {. h9 O& l9 j! N% F
/** */ /**' \, E! _1 B- i+ O: j4 ] O+ O
*
$ t2 {3 t1 W: [0 f * Title: LoonFramework$ I; ?& }9 e: u- q4 g8 W6 ~$ u5 M
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* Description:5 p6 b9 l r8 k* e) I
*
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( ]4 Q, Q8 i" e; W0 [ * Copyright: Copyright (c) 20079 M% s. r6 T+ O; i8 f/ Y# Z) J
*
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* Company: LoonFramework
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* @author chenpeng7 L+ G/ ^$ K) Q+ \
* @email:ceponline@yahoo.com.cn
( z, d# S; h, M * @version 0.15 L. \/ Q, B; h+ K' M
*/
) `$ z8 a$ o+ |4 v# O8 i public class ThreadPool ... {
( S- E/ ]) s( f7 h. ?+ P- A1 r3 G+ z private static ThreadPool instance = null ;' B# f7 y$ u9 Q. c
// 优先级低+ a9 K% o' g! H' A) X; q1 Z( L+ O
public static final int PRIORITY_LOW = 0 ;0 [ t+ Y; o. T( [
// 通俗
" b% z8 |1 {# L( [) {2 `( o' _ x public static final int PRIORITY_NORMAL = 1 ;
4 e+ o9 Y, ~3 R! e4 j9 v$ F // 高
7 T2 p l8 ~5 i( r$ j public static final int PRIORITY_HIGH = 2 ;: D- N' V/ |2 l, _7 o
// 用以保留余暇毗连" n' k K# y3 f! \
private List[] _idxThreads;
/ d. I6 N5 v3 \3 s // 封锁
9 B' ~6 |2 S1 [7 j, Z, Z private boolean _shutdown = false ;
# l; p! m+ \: C2 s // 线程数目
4 z9 W' v" S1 f3 r5 m1 c private int _threadCount = 0 ;
3 ~1 b5 S9 L( _8 |% A7 N i* P8 X // debug信息是否输出: H% M& f. b* _7 @' B( e! |3 L
private boolean _debug = false ;
. P3 [% S" J& h /** */ /**6 [$ V% J- { f7 f: n7 Z
* 返回ThreadPool实例
0 ]) I* F* q+ G0 N7 _' N *
, L: Q/ ^ t% @6 d/ p* e/ Z * @return8 J/ c$ e( V% b" l' b4 H2 A9 @, o# U
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public static ThreadPool getInstance() ... {
) J! d8 _, X/ x$ P ] if (instance == null ) ... {
/ J- i G1 }) \ instance = new ThreadPool();
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return instance;
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// 初始化线程list
) j/ D. P4 d% z+ ?1 ~0 r private ThreadPool() ... {: Q, ^' x( g* [( e5 i$ G( g7 u
this ._idxThreads = new List[] ... { new LinkedList(), new LinkedList(),, E: v3 ^- i* _7 k( t
new LinkedList() } ;
R- v$ e4 J, o u: i8 r this ._threadCount = 0 ;
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/** */ /** ~ f* F' c1 x1 P( l
* 同步体例,完成使命后将资本放回线程池中2 y5 H7 p5 [6 z' Z5 H/ @2 ~! K1 z
* @param repool
2 ^* r; i$ C3 \ */
- F- i4 `2 j/ E1 M) w protected synchronized void repool(Pooled repool) ... {+ b9 d# n4 b. S) _
if ( this ._shutdown) ... {2 E4 ]9 }1 u7 d2 r4 a6 U( T
if ( this ._debug) ... {5 z2 w& d* Z* W3 e
System.out.println( " ThreadPool.repool():重设中…… " );
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, m* K/ ~8 o! i8 [/ D; _ // 优先级别剖断! N8 f5 C: Y6 H e# d- d
switch (repool.getPriority()) ... {
" K: H: O/ w2 Y- Q4 I; I/ d3 g" Y case Thread.MIN_PRIORITY:
* ~) l7 K5 p& J3 q2 L @. H9 | R this ._idxThreads[PRIORITY_LOW].add(repool);
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case Thread.NORM_PRIORITY:
6 _* T: m' Z' k- } this ._idxThreads[PRIORITY_NORMAL].add(repool);
! T! S6 a6 m0 \; V4 d break ;& m" f# Y3 c: U8 X* L; t7 J
case Thread.MAX_PRIORITY:4 c2 d% Q$ u9 t) i4 B1 j' Z
this ._idxThreads[PRIORITY_HIGH].add(repool);# `: k4 ]; p E4 s0 Q( I
break ;
9 z9 e, t" Q. Z6 {' L5 u4 o0 F default :2 l% o! W1 G. }4 d- @- ]
throw new IllegalStateException( " 没有此种级别 " );" |" K, B5 _6 i- D
}
2 l# C: e: g6 } // 通知所有线程% ` S9 c/ r' H; t4 ~& X$ Q& \
notifyAll();& D$ L9 s; }5 s% _* G$ L& k
} else ... {9 V4 V( g N' N; y+ S, t
if ( this ._debug) ... {' e" P2 ]! m5 `! l% V* V3 d9 l, l
System.out.println( " ThreadPool.repool():注销中…… " );- Y# Z- S9 b5 x) T
}
0 f# f& r m8 d8 M; w2 R repool.shutDown();2 a- ]0 H! f r! o
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if ( this ._debug) ... {
! a! t- }- k# } System.out.println( " ThreadPool.repool():完成 " );5 Z' h$ R1 v0 o8 w ~/ G
}
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public void setDebug( boolean debug) ... {9 o. w& {- B7 v, X+ I
this ._debug = debug;( C" X0 ~7 B. r
}
9 i/ w7 |& I( B! } public synchronized void shutDown() ... {
9 j' d% r' O" v2 g# I: Y8 y z; ? this ._shutdown = true ;# u! A& x2 p( F* d
if ( this ._debug) ... {
0 a$ y0 C z- r. ^* b4 w& I2 v5 u& G" M System.out.println( " ThreadPool.shutDown():封锁中…… " );& u3 F6 D; B( U
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for ( int index = 0 ;index |