有时候在PHP程序中同时只允许一个进程在操作或者只想让一个进程去执行，这时就需要加锁，在网络上找到了phplock这个项目。phplock用于多进程模式下PHP并发操作加锁，以防止并发对同一文件的读写操作错误和缓存失效时，大量请求直接穿透到数据库，造成数据库压力宕机。
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PHP并发操作加锁
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PHP异步执行长时间任务
长时间执行的任务不适合放在PHP中执行应当放在任务调度系统或消息系统中由后台程序去执行，但是有时候还是需要在PHP中执行下长时间的任务 ，并且客户端不需要返回值。实现的思路大体如下：首先客户端发起一个不需要等待返回的请求，服务器端则需要忽略请求中断和执行时间，以免中途退出。
当有请求到达时，服务器端执行任务，在这里会产生一个文件。服务器端文件：
<?php
//ob_start();
//header('Content-Type:text/html;charset=utf-8');
//header('Connection:close');
//flush();
ignore_user_abort(true);//忽略客户端连接中断
set_time_limit(0);//忽略页面执行超时
//Todo:do something here
sleep(10);
fopen(dirname( __FILE__ ).'\\'.time(), "w");
[/php]
1.使用<a href="http://php.net/manual/en/function.fsockopen.php">fsockopen</a>来请求服务端执行任务，该方法需要自己拼凑header，包括参数等
<?php
function triggerRequest($url, $post_data = array(), $cookie = array()){
$method = "GET"; //可以通过POST或者GET传递一些参数给要触发的脚本
$url_array = parse_url($url); //获取URL信息，以便平凑HTTP HEADER
$port = isset($url_array['port'])? $url_array['port'] : 80;
$fp = fsockopen($url_array['host'], $port, $errno, $errstr, 30);
if (!$fp){
return FALSE;
}
$getPath = $url_array['path'] ."?". $url_array['query'];
if(!empty($post_data)){
$method = "POST";
}
$header = $method . " " . $getPath;
$header .= " HTTP/1.1\r\n";
$header .= "Host: ". $url_array['host'] . "\r\n "; //HTTP 1.1 Host域不能省略
$header .= "Connection:Close\r\n\r\n";
if(!empty($cookie)){
$_cookie = strval(NULL);
foreach($cookie as $k =--> $v){
$_cookie .= $k."=".$v."; ";
}
$cookie_str = "Cookie: " . base64_encode($_cookie) ." \r\n";//传递Cookie
$header .= $cookie_str;
}
if(!empty($post_data)){
$_post = strval(NULL);
foreach($post_data as $k => $v){
$_post .= $k."=".$v."&";
}
$post_str = "Content-Type: application/x-www-form-urlencoded\r\n";//POST数据
$post_str .= "Content-Length: ". strlen($_post) ." \r\n";//POST数据的长度
$post_str .= $_post."\r\n\r\n "; //传递POST数据
$header .= $post_str;
}
fwrite($fp, $header);
fclose($fp);
return true;
}
$url='http://127.0.0.1/learn/asyn/server.php';
triggerRequest($url);
2.使用curl来发起请求，可以方便的设置传递参数，cookie等，比fsockopen简洁许多，需要安装php_curl扩展
<?php
$ch = curl_init();
$data = array('param' => '1');
curl_setopt($ch, CURLOPT_URL, 'http://127.0.0.1/learn/asyn/server.php');
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
curl_setopt($ch, CURLOPT_TIMEOUT, 1);//1秒后立即执行
curl_exec($ch);
curl_close($ch);
也可以采用popen，ajax发起请求，详见参考链接。
参考链接
fsockopen函数用法
使用fscok实现异步调用PHP
PHP实现异步调用方法研究
说说php的异步请求
php curl常用的5个例子
Nginx做简单的反向代理
JasperReports flash打印实现
JasperReports是一个基于Java的开源报表工具，可以在ireport中进行设计后，输出HTML，PDF，Excell，OpenOffice和Word格式。JasperReports支持applet方式打印，但是flash方式却是注释掉的。在net\sf\jasperreports\flex\view\Viewer.mxml文件中
<!--
<mx:Button width="22" toolTip="Print Report" id="btnPrintReport0"
buttonMode="true"enabled="false" >
<mx:icon>@Embed(source='images/print.GIF')</mx:icon>
</mx:Button>
<mx:Button width="22" toolTip="Print Report" id="btnReload"
buttonMode="true" enabled="true" click="btnReloadClick()">
<mx:icon>@Embed(source='images/reload.GIF')</mx:icon>
</mx:Button>
-->
本文主要完成JasperReports的flash打印功能，是基于JasperReports Flash Viewer 4.0.0修改，参考了网络上基于3.0版本的修改。将Viewer.mxml文件上面的文字修改为
<mx:Button width="22" toolTip="Print Report" id="btnPrintReport0"
buttonMode="true" enabled="false" click="btnPrintReport()">
<mx:icon>@Embed(source='images/print.GIF')</mx:icon>
</mx:Button>
<!--
<mx:Button width="22" toolTip="Print Report" id="btnReload"
buttonMode="true" enabled="true" click="btnReloadClick()">
<mx:icon>@Embed(source='images/reload.GIF')</mx:icon>
</mx:Button>
-->
在Viewer.mxml中找到refreshPage函数，启用打印按钮，将
if (report.pageCount > 0)
{
var pageCanvas:PageCanvas = new PageCanvas(report.pages[pageIndex]);
pageCanvas.scaleX = zoomRatio;
pageCanvas.scaleY = zoomRatio;
pageBox.visible = false;
pageBox.removeAllChildren();
pageBox.addChild(pageCanvas);
pageBox.visible = true;
}
修改为
if (report.pageCount > 0)
{
var pageCanvas:PageCanvas = new PageCanvas(report.pages[pageIndex]);
pageCanvas.scaleX = zoomRatio;
pageCanvas.scaleY = zoomRatio;
pageBox.visible = false;
pageBox.removeAllChildren();
pageBox.addChild(pageCanvas);
pageBox.visible = true;
btnPrintReport0.enabled = true;
}
在Viewer.mxml中引入net\sf\jasperreports\flex\view\PrintMananger.as文件，以支持打印
import net.sf.jasperreports.flex.view.PrintManager;
在Viewer.mxml增加打印函数btnPrintReport
public function btnPrintReport():void
{
PrintManager.printAll(jrpxmlUrl,pageFetchSize,report);
}
net\sf\jasperreports\flex\view\PrintMananger.as文件内容
package net.sf.jasperreports.flex.view
{
import flash.events.EventDispatcher;
import flash.events.SecurityErrorEvent;
import flash.events.Event;
import flash.events.ProgressEvent;
import mx.core.UIComponent;
import mx.collections.IList;
import mx.collections.ArrayCollection;
import net.sf.jasperreports.flex.view.PageCanvas;
import net.sf.jasperreports.flex.model.Report;
import net.sf.jasperreports.flex.xml.ReportFactory;
import flash.events.HTTPStatusEvent;
import flash.net.URLLoader;
import flash.net.URLRequest;
import flash.events.IOErrorEvent;
import mx.printing.FlexPrintJobScaleType;
import mx.printing.FlexPrintJob;
import mx.core.Application;
import mx.containers.VBox;
import mx.events.FlexEvent;
public class PrintManager extends EventDispatcher
{
private var url:String;
private var urlLoader:URLLoader;
private var report:Report;
private var pageIndex:int = 0;
private var pageFetchSize:int = 1;
private var componentsToBeInitialized:int = 0;
private var pagesPrint:Array = [];
public const LOAD_PAGE:String="loadPage";
public const ALL_PAGE:String = "allPageLoader";
public function PrintManager(){
super();
}
public function get url():String
{
return url;
}
public function set url(value:String):void
{
url=value;
}
public function set fetchSize(fetchSize:int):void
{
pageFetchSize = fetchSize;
}
public static function printAll(url:String,fetchSize:int,report:Report):void
{
var pm:PrintManager = new PrintManager();
pm.url = url;
pm.pageFetchSize = fetchSize;
pm.report = report;
pm.loadAll();
}
private function loadAll():void
{
this.addEventListener(LOAD_PAGE, onLoadPage);
this.addEventListener(ALL_PAGE, onAllPageLoaded);
pageIndex=0;
if (report)
{
var loadFlag:Boolean=false;
while (pageIndex < report.pageCount) {
if (!report.pages[pageIndex]) {
loadFlag=true;
break;
}
pageIndex++;
}
}
if (loadFlag) {
loadPage();
}
else{
removeEventListener(LOAD_PAGE, onLoadPage);
dispatchEvent(new Event(ALL_PAGE));
}
}
private function onLoadPage(e:Event):void
{
pageIndex++;
if (pageIndex < report.pageCount) {
if(!report.pages[pageIndex]){
loadPage();
}
}
else{
removeEventListener(LOAD_PAGE, onLoadPage);
dispatchEvent(new Event(ALL_PAGE));
}
}
public function onAllPageLoaded(event:Event):void
{
var cur:int;
var uc:UIComponent;
var pj:*;
if (report != null){
pj = new FlexPrintJob();
pj.printAsBitmap = false;
if (pj.start()){
cur = 0;
while (cur < report.pageCount) {
uc = processPage(new PageCanvas(report.pages[cur]));
Application.application.addChild(uc);
pj.addObject(uc);
Application.application.removeChild(uc);
cur++;
};
pj.send();
};
} else {
};
}
private function processPage(param1:PageCanvas):UIComponent{
var vbox:* = new VBox();
vbox.horizontalScrollPolicy = "off";
vbox.verticalScrollPolicy = "off";
vbox.width = report.pageWidth;
vbox.height = report.pageHeight;
vbox.setStyle("backgroundColor", "#FFFFFF");
vbox.addChild(param1);
return (vbox);
}
private function loadPage():void
{
urlLoader=new URLLoader();
urlLoader.addEventListener(Event.COMPLETE, completeHandler);
urlLoader.addEventListener(Event.OPEN, openHandler);
urlLoader.addEventListener(ProgressEvent.PROGRESS, progressHandler);
urlLoader.addEventListener(SecurityErrorEvent.SECURITY_ERROR, securityErrorHandler);
urlLoader.addEventListener(HTTPStatusEvent.HTTP_STATUS, httpStatusHandler);
urlLoader.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
if (report)
{
var goRight:Boolean = true;
var goLeft:Boolean = true;
var right:int = 0;
var left:int = 0;
while(goRight || goLeft)
{
if (
goRight
&& left + right + 1 < pageFetchSize
&& pageIndex + right + 1 < report.pageCount
&& !report.pages[pageIndex + right + 1]
)
{
right++;
}
else
{
goRight = false;
}
if (
goLeft
&& left + right + 1 < pageFetchSize
&& pageIndex - left - 1 >= 0
&& !report.pages[pageIndex - left - 1]
)
{
left++;
}
else
{
goLeft = false;
}
}
urlLoader.load(new URLRequest(url + "&startPage=" + (pageIndex - left) + "&endPage=" + (pageIndex + right)));
}
else
{
//first load; pageIndex == 0
urlLoader.load(new URLRequest(url + "&page=" + pageIndex));
}
}
private function completeHandler(event:Event):void
{
var newReport:Report = ReportFactory.create(XML(urlLoader.data));
var i:int;
var pages:IList;
if (report)
{
pages = report.pages;
}
else
{
//first load
report = newReport;
pages = new ArrayCollection(new Array(report.pageCount));
}
for(i = newReport.startPageIndex; i <= newReport.endPageIndex; i++)
{
pages[i] = newReport.pages[i - newReport.startPageIndex];
}
report.pages = pages;
report.startPageIndex = Math.min(report.startPageIndex, newReport.startPageIndex);
report.endPageIndex = Math.max(report.endPageIndex, newReport.endPageIndex);
refreshPage();
}
private function openHandler(event:Event):void
{
trace("openHandler: " + event);
}
private function progressHandler(event:ProgressEvent):void
{
trace("progressHandler loaded:" + event.bytesLoaded + " total: " + event.bytesTotal);
}
private function securityErrorHandler(event:SecurityErrorEvent):void
{
trace("securityErrorHandler: " + event);
}
private function httpStatusHandler(event:HTTPStatusEvent):void
{
trace("httpStatusHandler: " + event);
}
private function ioErrorHandler(event:IOErrorEvent):void
{
trace("ioErrorHandler: " + event);
}
private function refreshPage():void
{
if (report) {
this.dispatchEvent(new Event(this.LOAD_PAGE));
}
}
}
}
编译Main.mxml运行，即实现打印功能，但是包含图片的打印依然打印不出来。对于这种动态图片的打印添加了等待事件完成，仍能无效，不知道有没有好的实现。
参考链接：
JasperReports Library
完成Flex报表设计、生成、打印功能
Flex 4 Printing Problem with dynamic components
PHP/Java Bridge笔记
PHP/Java Bridge是基于xml的网络协议的实现，该协议使得本地脚本语言引擎（ 比如PHP,Python）能够连接Java虚拟机。它比通过SOAP的RPC调用更快，更节省服务器资源；比直接的Java本地接口通信要更快和更可靠，不需要额外的组件。Java应用比PHP要多，组件和类库也比PHP要多，比如JasperReports，通过PHP/Java Bridge可以为PHP 所用，当然也可以采用其他方式进行调用,比如官方的SOAP示例。
网上的关于JavaBridge安装文章较旧，现在的JavaBridge安装已经不需要java.so或php_java.dll，只需要php安装版本大于5.0，JDK版本大于1.4.2。本文是将JavaBridge放在Tomcat下运行的，独立运行参照此文设置。 继续阅读