SAE-servlet---服务器端程序编写
我采用的是java servlet，最开始在本机tomcat上运行，后来发现SAE是jetty的环境，又去部署了jetty，而且把JRE版本改为了1.7
现在是在阿里云上部署，直接通过阿里云上安装的tomcat进行部署应用。
关于SAE怎么部署servlet，可以参考：
http://blog.csdn.net/u011680118/article/details/43566801
边写程序的时候边查了一下资料，感觉自己的java基础比较差，所以好多常用的东西还是记下来为好。
一、我用map是保存一些需要长期保持的，比如静态的编号名称对应关系等。
Map的一般用法
1.声明一个Map:
Map map = new HashMap();
2.向map中放值，注意： map是key-value的形式存放的，如：
map.put("sa","dd");
3.从map中取值:
String str =map.get("sa").toString,
结果是： str ="dd'
4.遍历一个map,从中取得key和value:
Map m= new HashMap();
for(Object obj :map.keySet()){
Object value = map.get(obj );
}
Map<String, Integer> city = new HashMap<String, Integer>();
二、字符串操作
String
取子串：substring
按指定字符分隔：split 返回的是一个字符串数组
找index： indexOf,lastIndexOf (可以用来帮助判断是否包含某个子串)
设定某个字符： setCharAt
StringBuffer (更适合多次修改的字符串)
StringBuffer SitesInfo = new StringBuffer();
清空： setLength(0); delete(0,sb.length());
替换： replace
获取当前时间的时与分：
int time = Integer.parseInt(new SimpleDateFormat("HHmm").format(new Date()));
获取html:
/**
* @throws Exception
*
* @Title: getHtml
* @Description: TODO(java得到html,网页采用 utf-8编码)
* @param: urlString
* @return: String
* @throws
*/
public static String getHtml(String urlString) throws Exception {
//System.out.println("GET HTML---" + new SimpleDateFormat("yyyy/MM/dd HH:mm:ss").format(new Date()));
StringBuffer html = new StringBuffer();
URL url = new URL(urlString);
//System.out.println(url);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setDoOutput(true);
conn.setUseCaches(false);
//设置连接超时的毫秒数
conn.setConnectTimeout(10000);
conn.setReadTimeout(20000);
//指定UTF-8编码，解决中文乱码问题
String coding = "UTF-8";
//conn.connect();
//String coding = "GBK";
InputStreamReader isr = new InputStreamReader(conn.getInputStream(),coding);
BufferedReader br = new BufferedReader(isr);
String temp;
while ((temp = br.readLine()) != null) {
//html.append(temp).append("\n");
html.append(temp);
//System.out.print(temp+"\n");
}
br.close();
isr.close();
return html.toString();
/*}
catch (Exception e) {
//e.printStackTrace();
System.out.println("html get error!");
return "";
}*/
}
去除HTML标签：
/**
* 定义script的正则表达式
* 定义style的正则表达式
* 定义HTML标签的正则表达式
*/
private static final String regEx_script = "<script[^>]*?>[\\s\\S]*?<\\/script>";
private static final String regEx_style = "<style[^>]*?>[\\s\\S]*?<\\/style>";
private static final String regEx_html = "<[^>]+>";
/**
* @Title: delHTMLTag
* @Description: TODO(去除HTML标签)
* @param: htmlStr
* @return: String
* @throws
*/
public String delHTMLTag(String htmlStr) {
//System.out.println("DEL HTML---" + new SimpleDateFormat("yyyy/MM/dd HH:mm:ss").format(new Date()));
Pattern p_script = Pattern.compile(regEx_script, Pattern.CASE_INSENSITIVE);
Matcher m_script = p_script.matcher(htmlStr);
htmlStr = m_script.replaceAll(""); // 过滤script标签
Pattern p_style = Pattern.compile(regEx_style, Pattern.CASE_INSENSITIVE);
Matcher m_style = p_style.matcher(htmlStr);
htmlStr = m_style.replaceAll(""); // 过滤style标签
Pattern p_html = Pattern.compile(regEx_html, Pattern.CASE_INSENSITIVE);
Matcher m_html = p_html.matcher(htmlStr);
htmlStr = m_html.replaceAll(""); // 过滤html标签
return htmlStr.trim(); // 返回文本字符串
}
中文转成拼音类：
//中文转成拼音类
class ChineseSpelling {
private static int[] pyvalue = new int[] { -20319, -20317, -20304, -20295, -20292, -20283, -20265, -20257, -20242, -20230, -20051, -20036, -20032, -20026, -20002, -19990, -19986, -19982, -19976, -19805, -19784, -19775, -19774, -19763, -19756, -19751, -19746, -19741, -19739, -19728, -19725, -19715, -19540, -19531, -19525, -19515, -19500, -19484, -19479, -19467, -19289, -19288, -19281, -19275, -19270, -19263, -19261, -19249, -19243, -19242, -19238, -19235, -19227, -19224, -19218, -19212, -19038, -19023, -19018, -19006, -19003, -18996, -18977, -18961, -18952, -18783, -18774, -18773, -18763, -18756, -18741, -18735, -18731, -18722, -18710, -18697, -18696, -18526, -18518, -18501, -18490, -18478, -18463, -18448, -18447, -18446, -18239, -18237, -18231, -18220, -18211, -18201, -18184, -18183,
-18181, -18012, -17997, -17988, -17970, -17964, -17961, -17950, -17947, -17931, -17928, -17922, -17759, -17752, -17733, -17730, -17721, -17703, -17701, -17697, -17692, -17683, -17676, -17496, -17487, -17482, -17468, -17454, -17433, -17427, -17417, -17202, -17185, -16983, -16970, -16942, -16915, -16733, -16708, -16706, -16689, -16664, -16657, -16647, -16474, -16470, -16465, -16459, -16452, -16448, -16433, -16429, -16427, -16423, -16419, -16412, -16407, -16403, -16401, -16393, -16220, -16216, -16212, -16205, -16202, -16187, -16180, -16171, -16169, -16158, -16155, -15959, -15958, -15944, -15933, -15920, -15915, -15903, -15889, -15878, -15707, -15701, -15681, -15667, -15661, -15659, -15652, -15640, -15631, -15625, -15454, -15448, -15436, -15435, -15419, -15416, -15408, -15394,
-15385, -15377, -15375, -15369, -15363, -15362, -15183, -15180, -15165, -15158, -15153, -15150, -15149, -15144, -15143, -15141, -15140, -15139, -15128, -15121, -15119, -15117, -15110, -15109, -14941, -14937, -14933, -14930, -14929, -14928, -14926, -14922, -14921, -14914, -14908, -14902, -14894, -14889, -14882, -14873, -14871, -14857, -14678, -14674, -14670, -14668, -14663, -14654, -14645, -14630, -14594, -14429, -14407, -14399, -14384, -14379, -14368, -14355, -14353, -14345, -14170, -14159, -14151, -14149, -14145, -14140, -14137, -14135, -14125, -14123, -14122, -14112, -14109, -14099, -14097, -14094, -14092, -14090, -14087, -14083, -13917, -13914, -13910, -13907, -13906, -13905, -13896, -13894, -13878, -13870, -13859, -13847, -13831, -13658, -13611, -13601, -13406, -13404,
-13400, -13398, -13395, -13391, -13387, -13383, -13367, -13359, -13356, -13343, -13340, -13329, -13326, -13318, -13147, -13138, -13120, -13107, -13096, -13095, -13091, -13076, -13068, -13063, -13060, -12888, -12875, -12871, -12860, -12858, -12852, -12849, -12838, -12831, -12829, -12812, -12802, -12607, -12597, -12594, -12585, -12556, -12359, -12346, -12320, -12300, -12120, -12099, -12089, -12074, -12067, -12058, -12039, -11867, -11861, -11847, -11831, -11798, -11781, -11604, -11589, -11536, -11358, -11340, -11339, -11324, -11303, -11097, -11077, -11067, -11055, -11052, -11045, -11041, -11038, -11024, -11020, -11019, -11018, -11014, -10838, -10832, -10815, -10800, -10790, -10780, -10764, -10587, -10544, -10533, -10519, -10331, -10329, -10328, -10322, -10315, -10309, -10307,
-10296, -10281, -10274, -10270, -10262, -10260, -10256, -10254 };
private static String[] pystr = new String[] { "a", "ai", "an", "ang", "ao", "ba", "bai", "ban", "bang", "bao", "bei", "ben", "beng", "bi", "bian", "biao", "bie", "bin", "bing", "bo", "bu", "ca", "cai", "can", "cang", "cao", "ce", "ceng", "cha", "chai", "chan", "chang", "chao", "che", "chen", "cheng", "chi", "chong", "chou", "chu", "chuai", "chuan", "chuang", "chui", "chun", "chuo", "ci", "cong", "cou", "cu", "cuan", "cui", "cun", "cuo", "da", "dai", "dan", "dang", "dao", "de", "deng", "di", "dian", "diao", "die", "ding", "diu", "dong", "dou", "du", "duan", "dui", "dun", "duo", "e", "en", "er", "fa", "fan", "fang", "fei", "fen", "feng", "fo", "fou", "fu", "ga", "gai", "gan", "gang", "gao", "ge", "gei", "gen", "geng", "gong", "gou", "gu", "gua", "guai", "guan", "guang", "gui", "gun",
"guo", "ha", "hai", "han", "hang", "hao", "he", "hei", "hen", "heng", "hong", "hou", "hu", "hua", "huai", "huan", "huang", "hui", "hun", "huo", "ji", "jia", "jian", "jiang", "jiao", "jie", "jin", "jing", "jiong", "jiu", "ju", "juan", "jue", "jun", "ka", "kai", "kan", "kang", "kao", "ke", "ken", "keng", "kong", "kou", "ku", "kua", "kuai", "kuan", "kuang", "kui", "kun", "kuo", "la", "lai", "lan", "lang", "lao", "le", "lei", "leng", "li", "lia", "lian", "liang", "liao", "lie", "lin", "ling", "liu", "long", "lou", "lu", "lv", "luan", "lue", "lun", "luo", "ma", "mai", "man", "mang", "mao", "me", "mei", "men", "meng", "mi", "mian", "miao", "mie", "min", "ming", "miu", "mo", "mou", "mu", "na", "nai", "nan", "nang", "nao", "ne", "nei", "nen", "neng", "ni", "nian", "niang", "niao",
"nie", "nin", "ning", "niu", "nong", "nu", "nv", "nuan", "nue", "nuo", "o", "ou", "pa", "pai", "pan", "pang", "pao", "pei", "pen", "peng", "pi", "pian", "piao", "pie", "pin", "ping", "po", "pu", "qi", "qia", "qian", "qiang", "qiao", "qie", "qin", "qing", "qiong", "qiu", "qu", "quan", "que", "qun", "ran", "rang", "rao", "re", "ren", "reng", "ri", "rong", "rou", "ru", "ruan", "rui", "run", "ruo", "sa", "sai", "san", "sang", "sao", "se", "sen", "seng", "sha", "shai", "shan", "shang", "shao", "she", "shen", "sheng", "shi", "shou", "shu", "shua", "shuai", "shuan", "shuang", "shui", "shun", "shuo", "si", "song", "sou", "su", "suan", "sui", "sun", "suo", "ta", "tai", "tan", "tang", "tao", "te", "teng", "ti", "tian", "tiao", "tie", "ting", "tong", "tou", "tu", "tuan", "tui", "tun",
"tuo", "wa", "wai", "wan", "wang", "wei", "wen", "weng", "wo", "wu", "xi", "xia", "xian", "xiang", "xiao", "xie", "xin", "xing", "xiong", "xiu", "xu", "xuan", "xue", "xun", "ya", "yan", "yang", "yao", "ye", "yi", "yin", "ying", "yo", "yong", "you", "yu", "yuan", "yue", "yun", "za", "zai", "zan", "zang", "zao", "ze", "zei", "zen", "zeng", "zha", "zhai", "zhan", "zhang", "zhao", "zhe", "zhen", "zheng", "zhi", "zhong", "zhou", "zhu", "zhua", "zhuai", "zhuan", "zhuang", "zhui", "zhun", "zhuo", "zi", "zong", "zou", "zu", "zuan", "zui", "zun", "zuo" };
private StringBuilder buffer;
private String resource;
private static ChineseSpelling chineseSpelling = new ChineseSpelling();
public static ChineseSpelling getInstance() {
return chineseSpelling;
}
public String getResource() {
return resource;
}
public void setResource(String resource) {
this.resource = resource;
}
private int getChsAscii(String chs) {
int asc = 0;
try {
byte[] bytes = chs.getBytes("gb2312");
if (bytes == null || bytes.length > 2 || bytes.length <= 0) { // 错误
// log
throw new RuntimeException("illegal resource string");
// System.out.println("error");
}
if (bytes.length == 1) { // 英文字符
asc = bytes[0];
}
if (bytes.length >= 2) { // 中文字符
int hightByte = 256 + bytes[0];
int lowByte = 256 + bytes[1];
asc = (256 * hightByte + lowByte) - 256 * 256;
}
}
catch (Exception e) {
System.out.println("ERROR:ChineseSpelling.class-getChsAscii(String chs)" + e);
// e.printStackTrace();
}
return asc;
}
public String convert(String str) {
String result = null;
int ascii = getChsAscii(str);
// System.out.println(ascii);
if (ascii > 0 && ascii < 160) {
result = String.valueOf((char) ascii);
} else {
for (int i = (pyvalue.length - 1); i >= 0; i--) {
if (pyvalue[i] <= ascii) {
result = pystr[i];
break;
}
}
}
return result;
}
public String getSelling(String chs) {
String key, value;
buffer = new StringBuilder();
for (int i = 0; i < chs.length(); i++) {
key = chs.substring(i, i + 1);
if (key.getBytes().length >= 2) {
value = (String) convert(key);
if (value == null) {
value = "unknown";
}
} else {
value = key;
}
buffer.append(value);
}
return buffer.toString();
}
public String getSpelling() {
return this.getSelling(this.getResource());
}
}
这么用：
//获取中文的拼音 ChineseSpelling finder = ChineseSpelling.getInstance(); finder.setResource(placeName); //System.out.println(finder.getSpelling());
三、使用连接池改善连接效率
连接池使用小结：
http://blog.csdn.net/bhq2010/article/details/9219947
连接池两种用法：
http://blog.sina.com.cn/s/blog_6c5f4d3c01012gtq.html
c3p0:
http://zc0604.iteye.com/blog/1160502
import java.beans.PropertyVetoException;
import java.sql.Connection;
import java.sql.SQLException;
import com.mchange.v2.c3p0.ComboPooledDataSource;
/**
* 数据库连接池
* 需要导入C30p jar
* @author xing
*
*/
public class C3P0Utils {
private static C3P0Utils dbcputils=null;
private ComboPooledDataSource cpds=null;
private C3P0Utils(){
if(cpds==null){
cpds=new ComboPooledDataSource();
}
//cpds.setUser(DBConsts.username);
//cpds.setPassword(DBConsts.password);
cpds.setJdbcUrl(DBConsts.url);
try {
cpds.setDriverClass(DBConsts.driverclass);
} catch (PropertyVetoException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
cpds.setInitialPoolSize(100);
cpds.setMaxIdleTime(20);
cpds.setMaxPoolSize(100);
cpds.setMinPoolSize(10);
}
public synchronized static C3P0Utils getInstance(){
if(dbcputils==null)
dbcputils=new C3P0Utils();
return dbcputils;
}
//返回连接池的一个连接
public Connection getConnection(){
Connection con=null;
try {
con=cpds.getConnection();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return con;
}
/*public synchronized void close(Connection conn)
{
try
{
if (conn != null)
{
conn.close();
conn = null;
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public synchronized void close(Statement stat)
{
try
{
if (stat != null)
{
stat.close();
stat = null;
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public synchronized void close(ResultSet rest)
{
try
{
if (rest != null)
{
rest.close();
rest = null;
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}*/
/*public static void main(String[] args) throws SQLException {
Connection con=null;
long begin=System.currentTimeMillis();
for(int i=0;i<1000000;i++){
con=C3P0Utils.getInstance().getConnection();
con.close();
}
long end=System.currentTimeMillis();
System.out.println("耗时为:"+(end-begin)+"ms");
}*/
}
//数据库连接配置
class DBConsts {
public static final String url=
"jdbc:mysql://localhost/stroll?user=root&password=";
//"jdbc:mysql://localhost/stroll?user=root&password=&characterEncoding=gbk";
public static final String driverclass="com.mysql.jdbc.Driver";
}
不用另外建立一次连接，直接使用ResultSet进行更新。
stmt = connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
rs = stmt.executeQuery(sql);
rs.next();
rs.getString("label");
rs.updateString("label",value);
rs.updateRow();
使用url参数传递:
req.getParameter();
注意传上去的文件的大小不能超过数据库限制，并且要对其中分隔符之间无内容（split会抛出异常）的情况进行异常处理。
附：
1.数据库字段详解：
http://blog.163.com/min_10yc1/blog/static/89532834201062291627506/
http://www.chinaz.com/program/2009/0105/59154.shtml
2.搭建phpmyadmin访问mysql:
http://www.chinabaike.com/z/shenghuo/pc/2011/0414/814363.html
http://www1.sitestar.cn/bbs/thread-164-1-1.html
3.安装mysql：
http://blog.sina.com.cn/s/blog_51b89c580101ma4b.html
四、Servlet中使用定时器
http://blog.sina.com.cn/s/blog_5165537f0100z7tl.html
使用更精准的频率更新：time.scheduleAtFixedRate(task, start,period);
@Override
public void destroy() {
// TODO Auto-generated method stub
//关闭数据库连接和定时器
time.cancel();
super.destroy();
}
@Override
public void init() throws ServletException {
// TODO Auto-generated method stub
super.init();
//设定定时更新开始时间为当天下午2：45分
Date start = new Date();
start.setDate(start.getDate());
start.setHours(14);
start.setMinutes(45);
start.setSeconds(0);
/*start.setHours(start.getHours());
start.setMinutes(start.getMinutes());
start.setSeconds(start.getSeconds()+30);*/
//15min
long period = 900*1000;
//开始时分
dataPeople.startdate = 0;//Integer.parseInt(new SimpleDateFormat("HHmm").format(start));;
time.scheduleAtFixedRate(task, start,period);
}
/**
* 设置定时运行程序
*/
Timer time = new Timer();
TimerTask task = new TimerTask()
{
@Override
public void run() {
//System.out.println("\n\nUPDATE---" + new SimpleDateFormat("yyyy/MM/dd HH:mm:ss").format(new Date()));
}
};
五、数据传输JSON
http://www.2cto.com/kf/201009/74381.html
我用的是 json-lib-2.4-jdk15.jar，到时候放进lib中就可以了。