@TLS private static long startTime;
@OnMethod(clazz="cd",method="Ҏ?/span>")
public static void onCall(){
println("enter this method");
startTime=timeMillis();
}
@OnMethod(clazz="cd",method="Ҏ?/span>",location=@Location(Kind.RETURN))
public static void onReturn(){
println("method end!");
println(strcat("Time taken ms",str(timeMillis()-startTime)));
}
}
btrace [pid] MethodResponseTime.class
q有例如获取调用参数、调用者的对象实例以及q回值等请参看User Guide?br />
btraceZ保持JVMq行的安全性，因此做了很多的限Ӟ例如不能抛出异常、修改传入的参数的倹{修改返回值等Q基本是一个只ȝ动态分析代码运? 状况的工P但仍然是非常的有用，其实现机制是attach api + asm + instrumentation?img src ="http://www.aygfsteel.com/Collus/aggbug/320789.html" width = "1" height = "1" />
]]>
]]>
/**
* FileUtil. Simple file operation class.
*
* @author BeanSoft
*
*/
public class FileUtil {
/**
* The buffer.
*/
protected static byte buf[] = new byte [ 1024 ];
/**
* Read content from local file. FIXME How to judge UTF-8 and GBK, the
* correct code should be: FileReader fr = new FileReader(new
* InputStreamReader(fileName, "ENCODING")); Might let the user select the
* encoding would be a better idea. While reading UTF-8 files, the content
* is bad when saved out.
*
* @param fileName -
* local file name to read
* @return
* @throws Exception
*/
public static String readFileAsString(String fileName) throws Exception {
String content = new String(readFileBinary(fileName));
return content;
}
/**
* d文gq返回ؓl定字符集的字符?
* @param fileName
* @param encoding
* @return
* @throws Exception
*/
public static String readFileAsString(String fileName, String encoding) throws Exception {
String content = new String(readFileBinary(fileName), encoding);
return content;
}
/**
* d文gq返回ؓl定字符集的字符?
* @param fileName
* @param encoding
* @return
* @throws Exception
*/
public static String readFileAsString(InputStream in) throws Exception {
String content = new String(readFileBinary(in));
return content;
}
/**
* Read content from local file to binary byte array.
*
* @param fileName -
* local file name to read
* @return
* @throws Exception
*/
public static byte [] readFileBinary(String fileName) throws Exception {
FileInputStream fin = new FileInputStream(fileName);
return readFileBinary(fin);
}
/**
* 从输入流d数据Zq制字节数组.
* @param streamIn
* @return
* @throws IOException
*/
public static byte [] readFileBinary(InputStream streamIn) throws IOException {
BufferedInputStream in = new BufferedInputStream(streamIn);
ByteArrayOutputStream out = new ByteArrayOutputStream( 10240 );
int len;
while ((len = in.read(buf)) >= 0 )
out.write(buf, 0 , len);
in.close();
return out.toByteArray();
}
/**
* Write string content to local file.
*
* @param fileName -
* local file name will write to
* @param content
* String text
* @return true if success
* @throws IOException
*/
public static boolean writeFileString(String fileName, String content)
throws IOException {
FileWriter fout = new FileWriter(fileName);
fout.write(content);
fout.close();
return true ;
}
/**
* Write string content to local file using given character encoding.
*
* @param fileName -
* local file name will write to
* @param content
* String text
* @param encoding
* the encoding
* @return true if success
* @throws IOException
*/
public static boolean writeFileString(String fileName, String content,
String encoding) throws IOException {
OutputStreamWriter fout = new OutputStreamWriter( new FileOutputStream(
fileName), encoding);
fout.write(content);
fout.close();
return true ;
}
/**
* Write binary byte array to local file.
*
* @param fileName -
* local file name will write to
* @param content
* binary byte array
* @return true if success
* @throws IOException
*/
public static boolean writeFileBinary(String fileName, byte [] content)
throws IOException {
FileOutputStream fout = new FileOutputStream(fileName);
fout.write(content);
fout.close();
return true ;
}
/**
* 查文件名是否合法.文g名字不能包含字符\/:*?"<>|
*
* @param fileName文g?不包含\?br /> * @return boolean is valid file name
*/
public static boolean isValidFileName(String fileName) {
boolean isValid = true ;
String errChar = " \\/:*?\ " <>| " ; //
if (fileName == null || fileName.length() == 0 ) {
isValid = false ;
} else {
for ( int i = 0 ; i < errChar.length(); i ++ ) {
if (fileName.indexOf(errChar.charAt(i)) != - 1 ) {
isValid = false ;
break ;
}
}
}
return isValid;
}
/**
* 把非法文件名转换为合法文件名.
*
* @param fileName
* @return
*/
public static String replaceInvalidFileChars(String fileName) {
StringBuffer out = new StringBuffer();
for ( int i = 0 ; i < fileName.length(); i ++ ) {
char ch = fileName.charAt(i);
// Replace invlid chars: \\/:*?\"<>|
switch (ch) {
case ' \\ ' :
case ' / ' :
case ' : ' :
case ' * ' :
case ' ? ' :
case ' \" ' :
case ' < ' :
case ' > ' :
case ' | ' :
out.append( ' _ ' );
break ;
default :
out.append(ch);
}
}
return out.toString();
}
/**
* Convert a given file name to a URL(URI) string.
*
* @param fileName -
* the file to parse
* @return - URL string
*/
public static String filePathToURL(String fileName) {
String fileUrl = new File(fileName).toURI().toString();
return fileUrl;
}
/**
* Write string content to local file.
*
* @param fileName -
* local file name will write to
* @param content
* String text
* @return true if success
* @throws IOException
*/
public static boolean appendFileString(String fileName, String content)
throws IOException {
OutputStreamWriter fout = new OutputStreamWriter( new FileOutputStream(
fileName, true ), " GBK " );
fout.write(content);
fout.close();
return true ;
}
public static void main(String[] args) {
System.out.println(replaceInvalidFileChars( " http://www.abc.com/ " ));
}
}
]]>
实际上，q个错误的原因，主要q是代码问题引v的。?br /> ORA-01000: maximum open cursors exceededQ表C已l达C个进E打开的最大游标数?
q样的错误很Ҏ出现在Java代码中的主要原因是：Java代码在执 行conn.createStatement()和conn.prepareStatement()的时候，实际上都是相当与在数据库中打开了一? cursor。尤其是Q如果你的createStatement和prepareStatement是在一个@环里面的话，׃非常Ҏ出现q个问题。因 为游标一直在不停的打开Q而且没有关闭?/span>
一般来_在写Java代码的时候，createStatement和prepareStatement都应该要攑֜循环外面Q而且使用了这? Statment后，及时关闭。最好是在执行了一ơexecuteQuery、executeUpdate{之后，如果不需要用结果集 QResultSetQ的数据Q就马上Statment关闭。?br />
对于出现ORA-01000错误q种情况Q单U的加大open_cursorsq不是好办法Q那只是L不治本。实际上Q代码中的隐患ƈ没有解除。?br /> 而且Q绝大部分情况下Qopen_cursors只需要设|一个比较小的|p够用了Q除非有非常特别的要求?
oracle 9i 默认的open_cursors=300
一、看有问题的代码
2 import java.sql.DriverManager;
3 import java.sql.SQLException;
4 import java.sql.Statement;
5
6 public class Test {
7 public Connection getConnection() {
8 String url = "jdbc:oracle:thin:@localhost:1521:ora9i";
9 String user = "scott";
10 String password = "tiger";
11 Connection con = null;
12 try {
13 Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
14 con = DriverManager.getConnection(url, user, password);
15 } catch (Exception e) {
16 e.printStackTrace();
17 }
18 return con;
19 }
20
21 public static void main(String[] args) throws SQLException {
22 long a = 13819100000L;
23 long b = 13819100600L; // 问题?/span>
24 Connection con = null;
25 Statement stmt = null;
26 Test insert = new Test();
27 try {
28 con = insert.getConnection();
29 for (long c = a; c <= b; c++) {
30 String sql = "insert into telepnum values(" + c + ")";
31 stmt = con.createStatement(); // q里是问题的所?/span>
32 stmt.executeUpdate(sql);
33 }
34 System.out.println("OK");
35 } catch (Exception e) {
36 e.printStackTrace();
37 } finally {
38 if (con != null) {
39 con.close();
40 }
41 }
42 }
43 }
二、分?/span>
在@环里面每ơ都 stmt = con.createStatement(); 而没有释放，q样每个都占用了一个服务器的游标资源，最后造成p|
三、解x?/span>
1、增加关闭语?
2 for (long c = a; c <= b; c++) {
3 String sql = "insert into telepnum values(" + c + ")";
4 stmt = con.createStatement(); // q里是问题的所?/span>
5 stmt.executeUpdate(sql);
6 stmt.close(); // 用完了就关闭好了
7 }
2、将q句话移动到循环外面Q推荐用q个
2 stmt = con.createStatement(); // Ud到这里，Statemet是可以重用的
3 for (long c = a; c <= b; c++) {
4 String sql = "insert into telepnum values(" + c + ")";
5 stmt.executeUpdate(sql);
6 }
7 stmt.close(); // 用完了就关闭好了
3、改装成扚w更新
2 con.setAutoCommit(false);
3 stmt = con.createStatement(); // Ud到这里，Statemet是可以重用的
4 for (long c = a; c <= b; c++) {
5 String sql = "insert into telepnum values(" + c + ")";
6 stmt.addBatch(sql);
7 }
8 stmt.executeBatch();
9 con.commit();
四、ȝ
鉴于上面的问题，在做基类的时候，在对数据q行DML操作的时候，量不要让基c返回Statement,而应该在基类直接q行关闭。在做查询的时候，? 以把statement留给E序员自p行手动关闭，关闭的方法ؓQ给ResultSet一个方法可以得到StatementQ然后再关闭 Statement。个U方法是比较妥当的?br />
]]>
函数列表Q?br />
/**
* 获取现在旉
*
* @return q回旉cd yyyy-MM-dd HH:mm:ss
*/
public static Date getNowDate() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
ParsePosition pos = new ParsePosition(8);
Date currentTime_2 = formatter.parse(dateString, pos);
return currentTime_2;
}
/**
* 获取现在旉
*
* @returnq回短时间格?yyyy-MM-dd
*/
public static Date getNowDateShort() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
String dateString = formatter.format(currentTime);
ParsePosition pos = new ParsePosition(8);
Date currentTime_2 = formatter.parse(dateString, pos);
return currentTime_2;
}
/**
* 获取现在旉
*
* @returnq回字符串格?yyyy-MM-dd HH:mm:ss
*/
public static String getStringDate() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
return dateString;
}
/**
* 获取现在旉
*
* @return q回短时间字W串格式yyyy-MM-dd
*/
public static String getStringDateShort() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
String dateString = formatter.format(currentTime);
return dateString;
}
/**
* 获取旉 时:?U?HH:mm:ss
*
* @return
*/
public static String getTimeShort() {
SimpleDateFormat formatter = new SimpleDateFormat("HH:mm:ss");
Date currentTime = new Date();
String dateString = formatter.format(currentTime);
return dateString;
}
/**
* 长旉格式字符串{换ؓ旉 yyyy-MM-dd HH:mm:ss
*
* @param strDate
* @return
*/
public static Date strToDateLong(String strDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
ParsePosition pos = new ParsePosition(0);
Date strtodate = formatter.parse(strDate, pos);
return strtodate;
}
/**
* 长旉格式旉转换为字W串 yyyy-MM-dd HH:mm:ss
*
* @param dateDate
* @return
*/
public static String dateToStrLong(java.util.Date dateDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(dateDate);
return dateString;
}
/**
* 短旉格式旉转换为字W串 yyyy-MM-dd
*
* @param dateDate
* @param k
* @return
*/
public static String dateToStr(java.util.Date dateDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
String dateString = formatter.format(dateDate);
return dateString;
}
/**
* 短旉格式字符串{换ؓ旉 yyyy-MM-dd
*
* @param strDate
* @return
*/
public static Date strToDate(String strDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
ParsePosition pos = new ParsePosition(0);
Date strtodate = formatter.parse(strDate, pos);
return strtodate;
}
/**
* 得到现在旉
*
* @return
*/
public static Date getNow() {
Date currentTime = new Date();
return currentTime;
}
/**
* 提取一个月中的最后一?br />
*
* @param day
* @return
*/
public static Date getLastDate(long day) {
Date date = new Date();
long date_3_hm = date.getTime() - 3600000 * 34 * day;
Date date_3_hm_date = new Date(date_3_hm);
return date_3_hm_date;
}
/**
* 得到现在旉
*
* @return 字符?yyyyMMdd HHmmss
*/
public static String getStringToday() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMdd HHmmss");
String dateString = formatter.format(currentTime);
return dateString;
}
/**
* 得到现在时
*/
public static String getHour() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
String hour;
hour = dateString.substring(11, 13);
return hour;
}
/**
* 得到现在分钟
*
* @return
*/
public static String getTime() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
String min;
min = dateString.substring(14, 16);
return min;
}
/**
* Ҏ用户传入的时间表C格式，q回当前旉的格?如果是yyyyMMddQ注意字母y不能大写?br />
*
* @param sformat
* yyyyMMddhhmmss
* @return
*/
public static String getUserDate(String sformat) {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat(sformat);
String dateString = formatter.format(currentTime);
return dateString;
}
/**
* 二个时旉间的差?必须保证二个旉都是"HH:MM"的格式，q回字符型的分钟
*/
public static String getTwoHour(String st1, String st2) {
String[] kk = null;
String[] jj = null;
kk = st1.split(":");
jj = st2.split(":");
if (Integer.parseInt(kk[0]) < Integer.parseInt(jj[0]))
return "0";
else {
double y = Double.parseDouble(kk[0]) + Double.parseDouble(kk[1]) / 60;
double u = Double.parseDouble(jj[0]) + Double.parseDouble(jj[1]) / 60;
if ((y - u) > 0)
return y - u + "";
else
return "0";
}
}
/**
* 得到二个日期间的间隔天数
*/
public static String getTwoDay(String sj1, String sj2) {
SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
long day = 0;
try {
java.util.Date date = myFormatter.parse(sj1);
java.util.Date mydate = myFormatter.parse(sj2);
day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
} catch (Exception e) {
return "";
}
return day + "";
}
/**
* 旉前推或后推分?其中JJ表示分钟.
*/
public static String getPreTime(String sj1, String jj) {
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String mydate1 = "";
try {
Date date1 = format.parse(sj1);
long Time = (date1.getTime() / 1000) + Integer.parseInt(jj) * 60;
date1.setTime(Time * 1000);
mydate1 = format.format(date1);
} catch (Exception e) {
}
return mydate1;
}
/**
* 得到一个时间g后或前移几天的时?nowdate为时?delay为前UL后g的天?br />
*/
public static String getNextDay(String nowdate, String delay) {
try{
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String mdate = "";
Date d = strToDate(nowdate);
long myTime = (d.getTime() / 1000) + Integer.parseInt(delay) * 24 * 60 * 60;
d.setTime(myTime * 1000);
mdate = format.format(d);
return mdate;
}catch(Exception e){
return "";
}
}
/**
* 判断是否润年
*
* @param ddate
* @return
*/
public static boolean isLeapYear(String ddate) {
/**
* 详细设计Q?1.?00整除是闰q_否则Q?2.不能?整除则不是闰q?3.能被4整除同时不能?00整除则是闰年
* 3.能被4整除同时能被100整除则不是闰q?br />
*/
Date d = strToDate(ddate);
GregorianCalendar gc = (GregorianCalendar) Calendar.getInstance();
gc.setTime(d);
int year = gc.get(Calendar.YEAR);
if ((year % 400) == 0)
return true;
else if ((year % 4) == 0) {
if ((year % 100) == 0)
return false;
else
return true;
} else
return false;
}
/**
* q回国旉格式 26 Apr 2006
*
* @param str
* @return
*/
public static String getEDate(String str) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
ParsePosition pos = new ParsePosition(0);
Date strtodate = formatter.parse(str, pos);
String j = strtodate.toString();
String[] k = j.split(" ");
return k[2] + k[1].toUpperCase() + k[5].substring(2, 4);
}
/**
* 获取一个月的最后一?br />
*
* @param dat
* @return
*/
public static String getEndDateOfMonth(String dat) {// yyyy-MM-dd
String str = dat.substring(0, 8);
String month = dat.substring(5, 7);
int mon = Integer.parseInt(month);
if (mon == 1 || mon == 3 || mon == 5 || mon == 7 || mon == 8 || mon == 10 || mon == 12) {
str += "31";
} else if (mon == 4 || mon == 6 || mon == 9 || mon == 11) {
str += "30";
} else {
if (isLeapYear(dat)) {
str += "29";
} else {
str += "28";
}
}
return str;
}
/**
* 判断二个旉是否在同一个周
*
* @param date1
* @param date2
* @return
*/
public static boolean isSameWeekDates(Date date1, Date date2) {
Calendar cal1 = Calendar.getInstance();
Calendar cal2 = Calendar.getInstance();
cal1.setTime(date1);
cal2.setTime(date2);
int subYear = cal1.get(Calendar.YEAR) - cal2.get(Calendar.YEAR);
if (0 == subYear) {
if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR))
return true;
} else if (1 == subYear && 11 == cal2.get(Calendar.MONTH)) {
// 如果12月的最后一周横跨来q第一周的话则最后一周即做来年的第一?br />
if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR))
return true;
} else if (-1 == subYear && 11 == cal1.get(Calendar.MONTH)) {
if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR))
return true;
}
return false;
}
/**
* 产生周序?卛_到当前时间所在的q度是第几周
*
* @return
*/
public static String getSeqWeek() {
Calendar c = Calendar.getInstance(Locale.CHINA);
String week = Integer.toString(c.get(Calendar.WEEK_OF_YEAR));
if (week.length() == 1)
week = "0" + week;
String year = Integer.toString(c.get(Calendar.YEAR));
return year + week;
}
/**
* 获得一个日期所在的周的星期几的日期Q如要找?002q??日所在周的星期一是几?br />
*
* @param sdate
* @param num
* @return
*/
public static String getWeek(String sdate, String num) {
// 再{换ؓ旉
Date dd = VeDate.strToDate(sdate);
Calendar c = Calendar.getInstance();
c.setTime(dd);
if (num.equals("1")) // q回星期一所在的日期
c.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
else if (num.equals("2")) // q回星期二所在的日期
c.set(Calendar.DAY_OF_WEEK, Calendar.TUESDAY);
else if (num.equals("3")) // q回星期三所在的日期
c.set(Calendar.DAY_OF_WEEK, Calendar.WEDNESDAY);
else if (num.equals("4")) // q回星期四所在的日期
c.set(Calendar.DAY_OF_WEEK, Calendar.THURSDAY);
else if (num.equals("5")) // q回星期五所在的日期
c.set(Calendar.DAY_OF_WEEK, Calendar.FRIDAY);
else if (num.equals("6")) // q回星期六所在的日期
c.set(Calendar.DAY_OF_WEEK, Calendar.SATURDAY);
else if (num.equals("0")) // q回星期日所在的日期
c.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
return new SimpleDateFormat("yyyy-MM-dd").format(c.getTime());
}
/**
* Ҏ一个日期，q回是星期几的字W串
*
* @param sdate
* @return
*/
public static String getWeek(String sdate) {
// 再{换ؓ旉
Date date = VeDate.strToDate(sdate);
Calendar c = Calendar.getInstance();
c.setTime(date);
// int hour=c.get(Calendar.DAY_OF_WEEK);
// hour中存的就是星期几了，其范?1~7
// 1=星期?7=星期六，其他cL
return new SimpleDateFormat("EEEE").format(c.getTime());
}
public static String getWeekStr(String sdate){
String str = "";
str = VeDate.getWeek(sdate);
if("1".equals(str)){
str = "星期?;
}else if("2".equals(str)){
str = "星期一";
}else if("3".equals(str)){
str = "星期?;
}else if("4".equals(str)){
str = "星期?;
}else if("5".equals(str)){
str = "星期?;
}else if("6".equals(str)){
str = "星期?;
}else if("7".equals(str)){
str = "星期?;
}
return str;
}
/**
* 两个旉之间的天?br />
*
* @param date1
* @param date2
* @return
*/
public static long getDays(String date1, String date2) {
if (date1 == null || date1.equals(""))
return 0;
if (date2 == null || date2.equals(""))
return 0;
// 转换为标准时?br />
SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
java.util.Date date = null;
java.util.Date mydate = null;
try {
date = myFormatter.parse(date1);
mydate = myFormatter.parse(date2);
} catch (Exception e) {
}
long day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
return day;
}
/**
* 形成如下的日?Q?Ҏ传入的一个时间返回一个结?星期?星期一 星期?星期?星期?星期?星期?下面是当月的各个旉
* 此函数返回该日历W一行星期日所在的日期
*
* @param sdate
* @return
*/
public static String getNowMonth(String sdate) {
// 取该旉所在月的一?br />
sdate = sdate.substring(0, 8) + "01";
// 得到q个月的1h星期?br />
Date date = VeDate.strToDate(sdate);
Calendar c = Calendar.getInstance();
c.setTime(date);
int u = c.get(Calendar.DAY_OF_WEEK);
String newday = VeDate.getNextDay(sdate, (1 - u) + "");
return newday;
}
/**
* 取得数据库主?生成格式为yyyymmddhhmmss+k位随机数
*
* @param k
* 表示是取几位随机敎ͼ可以自己?br />
*/
public static String getNo(int k) {
return getUserDate("yyyyMMddhhmmss") + getRandom(k);
}
/**
* q回一个随机数
*
* @param i
* @return
*/
public static String getRandom(int i) {
Random jjj = new Random();
// int suiJiShu = jjj.nextInt(9);
if (i == 0)
return "";
String jj = "";
for (int k = 0; k < i; k++) {
jj = jj + jjj.nextInt(9);
}
return jj;
}
]]>