Question

我们已经在jboss 4.0.2中部署了我们的Java EE Web应用程序（我们使用的是JDK 1.6.0_18）。

在我们的代码中，我们遍历Collection并在集合中执行userid的字符串连接（参见下面的代码）。

在生产服务器上，它的行为不一致。在最终字符串中找不到用户标识（2044157）（请参阅ServerLog第3行）。如果我们重新启动生产jboss服务器，那么它可以正常工作，并在最终字符串日志中正确打印所有用户。但是大量使用后（5-6小时后）问题再次出现。我们无法在质量保证环境中复制该问题。

当问题发生时，看起来indexOf方法错误地返回了strUsers字符串中的2044157（即使2044157不存在），因此它进入else部分并将其打印在else部分日志中（参见ServerLog）第2行 - 以粗体突出显示。这种不一致的行为可能是什么原因？

代码：

public class UsersEJB implements SessionBean{ 
     private void processSelectionData{ 
     StringBuilder strUsers = new StringBuilder(""); 
     Collection userVoCollection = dc.retProjectOrgUsers(projectID, strDistributionCompID, porjectDataSource); // This is returning List of 626 UserVO 
     if(log.isDebugEnabled()) 
         log.debug("UserList Size="+userVoCollection.size()+",B4 strUsers="+strUsers.toString()); 

     Iterator it = userVoCollection.iterator();

     while(it.hasNext()) { 
         UserVO uVO = (UserVO)it.next(); 
         if(!(strUsers.toString().indexOf("," + uVO.userID.toString() + ",") > -1)) { 
                 strUsers.append(uVO.userID.toString()).append(","); 
                 loopCntPos++; 
         } else { 
                 loopCntNeg++; 
                 if(log.isDebugEnabled()) 
                 log.debug("UserId="+uVO.userID.toString()+",strUsers="+loopCnt+"="+strUsers.toString());
         } 
         loopCnt++; 
     }

     if(log.isDebugEnabled()) 
         log.debug("COMPANIES_ID1 strUsers="+strUsers.toString() + ",### loopCnt="+loopCnt + ",loopCntPos="+loopCntPos + ",loopCntNeg="+loopCntNeg); 

    } 
}

ServerLog中

UserList Size = 626，B4 strUsers =，1732286,2066065,2096854,1952590,1731333,1732065,1734828,1852547,1732020,1733653,1731278,2079012,1733299,1765873,1733431,1960010,1828681,2047672,1731752， 1733172,1784314,1989311,1734795,1732658,1731415,1785285,1785185,1738446,1733139,1732526,1733549,1731078,1804055,1732939,1663167,1732768,1732029,1732504,1989185,1882746,1785428,1731213,1732931,1731296， 1733503,1753435,1731667,1936166,1747699,2099764,1482144,1747707,1732953,1771653,1731251,1989303,1755297,1731160,1901283,1782751,1733543,1882693,1733354,1974270,2044300,1732082,1907188,1731872,1955156， 1732153,1733260,1731096,1604035,1731914,1731169,1732418,1731240,1989180,1731306,1733533,1882684,1821306,1731178,1731389,1733309,1733104,2078768,1989277,1732542,1733513,1733082,1732630,1733289,1733361， 2077522,1733252,1732493,1978847,1733071，用户ID = 2044157，strUsers = 440 =，1732286,2066065,2096854,1952590,1731333,1732065,1734828,1852547,1732020,1733653,1731278,2079012,1733299,1765873,1733431,1960010,1828681,2047672,1731752,1733172,1784314 ，1989311,1734795,1732658,1731415,1785285,1785185,1738446,1733139,1732526,1733549,1731078,1804055,1732939,1663167,1732768,1732029,1732504,1989185,1882746,1785428,1731213,1732931,1731296,1733503,1753435 ，1731667,1936166,1747699,2099764,1482144,1747707,1732953,1771653,1731251,1989303,1755297,1731160,1901283,1782751,1733543,1882693,1733354,1974270,2044300,1732082,1907188,1731872,1955156,1732153,1733260 ，1731096,1604035,1731914,1731169,1732418,1731240,1989180,1731306,1733533,1882684,1821306,1731178,1731389,1733309,1733104,2078768,1989277,1732542,1733513,1733082,1732630,1733289,1733361,2077522,1733252 ，1732493,1978847,1733071,1893797,2137701,2025815,1522850,2027582,1732833,1984513,2037965,1900381,1731514,2044357,2042751,1785407,2118267,2050509,2062445,1934909,1912411,1733673,1731956,1694916,1731951 ，204 8024,1735552,2115155,1732777,2120796,2048007,1845970,1738356,1841988,2101099,2027667,2067876,1734628,1731739,1731893,2051612,1819645,1803654,2037906,1732047,1478544,2073677,2012435,2067977,2073669， 1981390,1731124,15916,6766,1978916,1732750,1936298,1891936,1747650,1949484,2101161,1928883,1948164,2013726,1750718,1732164,1733700,1639298,1734968,1732007,1734723,1949403,2137692,1990151,1734617， 2101130,1928888,2044163,1732042,1819543,2137672,1735463,1732716,1950975,2025826,1984507,2017645,1372949,1928719,1732684,1952358,1581015,2026878,1731622,1734036,2000528,1734611,2052691,1961286,2107121， 1733335,1868846,2000469,1734771,1841953,2118224,2038924,1731609,1735396,2026033,1805573,2107214,1638397,1731502,1731581,2115171,2120903,1892076,2060862,2017603,2002514,1731351,1901274,1760679,1821298， 1884485,1777244,1731204,1934917,2000497,1737101,2115043,2121909,2097818,1506144,1953947,1753401,1594875,2135263,1900276,1907168,1851867,1940057,1897000,1765857,2037953,1907085,2037911,2062548,1650062， 1801180， 1953696,2119602,1605403,1804076,1669286,1844334,1542596,2048001,1938656,1757959,1529666,2070447,1565121,1907065,1944060,2097808,2077490,1843170,1957289,1690800,1823148,1788987,1912477,1738344,1845866， 2047996,1962156,1483244,2071932,2127277,1912419,1756748,1999518,1908161,1722312,1548164,1584044,2047896,1856844,1762432,2073439,1861949,1530755,1989292,1852455,2027658,1738380,2067996,1981507,1998543， 1958859,1620837,1852555,2012357,1895444,2050380,1789210,1932156,1898948,2046841,2098171,1625335,2138533,2046655,1785464,2105080,2024935,1852446,2073682,1478644,2103660,1751154,1863254,1478332,1849259， 1593399,1895334,2075182,2134365,2136657， COMPANIES_ID1 strUsers =，1732286,2066065,2096854,1952590,1731333,1732065,1734828,1852547,1732020,1733653,1731278,2079012,1733299,1765873,1733431,1960010,1828681,2047672,1731752,1733172,1784314,1989311,1734795， 1732658,1731415,1785285,1785185,1738446,1733139,1732526,1733549,1731078,1804055,1732939,1663167,1732768,1732029,1732504,1989185,1882746,1785428,1731213,1732931,1731296,1733503,1753435,1731667,1936166， 1747699,2099764,1482144,1747707,1732953,1771653,1731251,1989303,1755297,1731160,1901283,1782751,1733543,1882693,1733354,1974270,2044300,1732082,1907188,1731872,1955156,1732153,1733260,1731096,1604035， 1731914,1731169,1732418,1731240,1989180,1731306,1733533,1882684,1821306,1731178,1731389,1733309,1733104,2078768,1989277,1732542,1733513,1733082,1732630,1733289,1733361,2077522,1733252,1732493,1978847， 1733071,1893797,2137701,2025815,1522850,2027582,1732833,1984513,2037965,1900381,1731514,2044357,2042751,1785407,2118267,2050509,2062445,1934909,1912411,1733673,1731956,1694916,1731951,2048024， 1735552,2115155,1732777,2120796,2048007,1845970,1738356,1841988,2101099,2027667,2067876,1734628,1731739,1731893,2051612,1819645,1803654,2037906,1732047,1478544,2073677,2012435,2067977,2073669,1981390， 1731124,15916,6766,1978916,1732750,1936298,1891936,1747650,1949484,2101161,1928883,1948164,2013726,1750718,1732164,1733700,1639298,1734968,1732007,1734723,1949403,2137692,1990151,1734617,2101130， 1928888,2044163,1732042,1819543,2137672,1735463,1732716,1950975,2025826,1984507,2017645,1372949,1928719,1732684,1952358,1581015,2026878,1731622,1734036,2000528,1734611,2052691,1961286,2107121,1733335， 1868846,2000469,1734771,1841953,2118224,2038924,1731609,1735396,2026033,1805573,2107214,1638397,1731502,1731581,2115171,2120903,1892076,2060862,2017603,2002514,1731351,1901274,1760679,1821298,1884485， 1777244,1731204,1934917,2000497,1737101,2115043,2121909,2097818,1506144,1953947,1753401,1594875,2135263,1900276,1907168,1851867,1940057,1897000,1765857,2037953,1907085,2037911,2062548,1650062,1801180， 19536 96,2119602,1605403,1804076,1669286,1844334,1542596,2048001,1938656,1757959,1529666,2070447,1565121,1907065,1944060,2097808,2077490,1843170,1957289,1690800,1823148,1788987,1912477,1738344,1845866， 2047996,1962156,1483244,2071932,2127277,1912419,1756748,1999518,1908161,1722312,1548164,1584044,2047896,1856844,1762432,2073439,1861949,1530755,1989292,1852455,2027658,1738380,2067996,1981507,1998543， 1958859,1620837,1852555,2012357,1895444,2050380,1789210,1932156,1898948,2046841,2098171,1625335,2138533,2046655,1785464,2105080,2024935,1852446,2073682,1478644,2103660,1751154,1863254,1478332,1849259， 1593399,1895334,2075182,2134365,2136657,2041203,2043944,2040358,2093521,1913544,2082455,2024959,2045812,1973980,1494485,1986446,1525605,2046849,1785194,1822210,2053401,1918823,2001794,1785258,2064339， 1986338,1710198,1521244,1822292,1931276,2134370,2075073,2134300,2075068,1521210,2131493,1951008,1914649,1774999,1601557,1485584,2078975,1986330,1612190,2064410,2066054,1985760,1685075,1930273,2032161， 19551 61 ,, ### loopCnt = 626，loopCntPos = 274，loopCntNeg = 352

Answer 1

目前，您的搜索不会选择第一个用户，因为之前没有逗号。但是，我建议使用set：

以更简单的方式解决问题

public class UsersEJB implements SessionBean
{ 
  private void processSelectionData
  { 
    Collection userVoCollection = dc.retProjectOrgUsers(projectID, strDistributionCompID, porjectDataSource); // This is returning List of 626 UserVO 
    Set<String> usersSet = new HashSet<String>(userVoCollection.size());

    if(log.isDebugEnabled()) 
      log.debug("UserList Size="+userVoCollection.size()+",B4 strUsers="+strUsers.toString()); 

    for (UserVO uVO : userVoCollection)
    {
      if (usersSet.add(uVO.userID.toString())
        loopCntPos++;
      else
      {
        loopCntNeg++;
        if(log.isDebugEnabled())
          log.debug("UserId="+uVO.userID.toString()+",strUsers="+loopCnt+"="+strUsers.toString());
    }


    if(log.isDebugEnabled()) 
      log.debug("COMPANIES_ID1 strUsers=" + usersSet + ",### loopCnt="+loopCnt + ",loopCntPos="+loopCntPos + ",loopCntNeg="+loopCntNeg);     
  } 
}

indexOf方法的奇怪行为

1 个答案: