jdcb查询SQL Server数据乱码问题解决方法

用jdcb查询SQL Server数据源数据时，在window环境下数据没有任何异常，但到linux环境下，英文和数字没有任何问题，但中文出现乱码，搜索SQLServer jdbc乱码原因，没有得到想要的答案，于是，从SQLServer驱动的实现开始，查找没有想Mysql配置url是，编码属性配置：
//SQLServerDriver

public Connection connect(String s, Properties properties)
        throws SQLServerException
    {
        try
        {
            Logger.setLogWriter(this, DriverManager.getLogWriter());
        }
        catch(NoSuchMethodError nosuchmethoderror)
        {
            Util.println("This version of sqlserver jdbc driver needs the JVM to support level 1.4 or higher");
            Util.println("The current JVM level is:" + Util.sJDKVersion);
            try
            {
                Logger.setLogStream(this, DriverManager.getLogStream());
            }
            catch(Exception exception) { }
        }
        SQLServerConnection sqlserverconnection = null;
	//解析URL
        Properties properties1 = Util.parseUrl(s);
        if(properties1 == null)
            return null;
        Object obj = null;
        Object obj1 = null;
        int i = DriverManager.getLoginTimeout();
        if(i > 0)
            properties1.put("loginTimeout", (new Integer(i)).toString());
        for(int j = 0; j < driverProperties.length; j++)
        {
            String s1 = driverProperties[j];
            if(properties1.getProperty(s1) != null)
                continue;
            String s2 = properties.getProperty(s1);
            if(s2 != null)
                properties1.put(s1, s2);
        }

        connProperties = properties1;
        String s3 = properties1.getProperty("logfile");
        if(s3 != null)
            Logger.setCustomLogFile(this, s3);
        sqlserverconnection = new SQLServerConnection();
        sqlserverconnection.sConnectURL = s;
        try
        {
	    //获取连接
            sqlserverconnection.connect(properties1, null);
        }
        catch(SQLException sqlexception)
        {
            throw new SQLServerException(sqlserverconnection, "Failed Logon:" + sqlexception.toString() + " url:" + s, sqlexception.getSQLState(), sqlexception.getErrorCode(), false);
        }
        return sqlserverconnection;
    }

先来看解析url：

Properties properties1 = Util.parseUrl(s);

//Util

public static Properties parseUrl(String s)
   {
       Properties properties = new Properties();
       String s1 = s;
       Object obj = null;
       Object obj1 = null;
       String s3 = "jdbc:sqlserver://";
       if(!s1.startsWith(s3))
           return null;
       s1 = s1.substring(s3.length());
       try
       {
           StringTokenizer stringtokenizer = new StringTokenizer(s1, ":/&?;", true);
           String s2 = stringtokenizer.nextToken();
           properties.put("serverName", s2);
           String s4 = stringtokenizer.nextToken();
           if(s4.equals(":"))
           {
               String s7 = stringtokenizer.nextToken();
               properties.put("portNumber", s7);
               String s5 = stringtokenizer.nextToken();
           }
           int i = 0;
           do
           {
               if(!stringtokenizer.hasMoreTokens())
                   break;
               String s6 = stringtokenizer.nextToken();
               if(++i % 2 != 0)
               {
                   StringTokenizer stringtokenizer1 = new StringTokenizer(s6, "=", true);
                   String s8 = stringtokenizer1.nextToken();
                   if(stringtokenizer1.hasMoreTokens())
                   {
                       stringtokenizer1.nextToken();
                       if(stringtokenizer1.hasMoreTokens())
                       {
                           String s9 = stringtokenizer1.nextToken();
                           properties.put(s8, s9);
                       }
                   } else
                   {
                       properties.put("databaseName", s8);
                   }
               }
           } while(true);
       }
       catch(NoSuchElementException nosuchelementexception) { }
       return properties;
}

没有找到字符编码相关的属性配置

再来看获取连接：
//SQLServerConnection

public Connection connect(Properties properties, BasePooledConnection basepooledconnection)
        throws SQLServerException
    {
        int k;
        ConnectionProperties connectionproperties;
        int l;
        int i1;
        int i2;
        activeConnectionProperties = properties;
        pooledConnectionParent = basepooledconnection;
        conPropertiesArray = new ConnectionProperties[10];
        for(int i = 0; i < 10; i++)
            conPropertiesArray[i] = new ConnectionProperties();
        String s = null;
        String s1 = null;
	//获取数据库连接属性配置
        s = properties.getProperty("enableFailover");
        boolean flag = s != null && s.equals("true");
        s = "user";
        s1 = properties.getProperty(s);
        if(s1 == null)
            s1 = "";
        buildConnectionProperties(s, s1, flag);
        s = "password";
        s1 = properties.getProperty(s);
        if(s1 == null)
            s1 = "";
        buildConnectionProperties(s, s1, flag);
        s = "databaseName";
        s1 = properties.getProperty(s);
        if(s1 == null)
            s1 = properties.getProperty("database");
        buildConnectionProperties(s, s1, flag);
        String s2 = s1;
        s = "serverName";
        s1 = properties.getProperty(s);
        if(s1 == null)
            s1 = properties.getProperty("host");
        if(s1 == null)
            s1 = "localhost";
        String s3 = s1;
        int j = s1.indexOf('\\');
        String s4 = null;
        if(j >= 0)
        {
            String s5 = s1.substring(j + 1, s1.length());
            s1 = s1.substring(0, j);
            s4 = getInstancePort(s1, s5);
        } else
        {
            String s6 = properties.getProperty("instanceName");
            if(s6 != null)
                s4 = getInstancePort(s1, s6);
        }
        buildConnectionProperties(s, s1, flag);
        s = "portNumber";
        s1 = properties.getProperty(s);
        if(s1 == null)
            s1 = properties.getProperty("port");
        if(s1 == null || s1.equals("0"))
            if(s4 == null)
                s1 = "1433";
            else
                s1 = s4;
        buildConnectionProperties(s, s1, flag);
        s = "sqlVersion";
        s1 = properties.getProperty(s);
        if(s1 == null)
            s1 = properties.getProperty("sqlversion");
        buildConnectionProperties(s, s1, flag);
        s = "asciiStringParameters";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "booleanLiterals";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "applicationName";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "instanceName";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "lastUpdateCount";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "disableStatementPooling";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "trustedAuthentication";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "codepage";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "loginTimeout";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "lockTimeout";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "xopenStates";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "enableFailover";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "selectMethod";
        s1 = properties.getProperty(s);
        if(s1 == null || !s1.equals("cursor"))
            s1 = "default";
        buildConnectionProperties(s, s1, flag);
        s = "preExecuteMetaData";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "iterativeBatching";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "connectionRetryCount";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "connectionRetryWait";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "trustedAuthenticationPort";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "ntlmAuthentication";
        s1 = properties.getProperty(s);
        buildConnectionProperties(s, s1, flag);
        s = "domain";
        s1 = properties.getProperty(s);
	...
}

仍然没有找到对应的字符编码相关属性：

那会是什么原因呢？

一想，在Mysql jdbc相关的文章中我们看到Mysql jdbc连接与客户端时通过socket的连接来通信的，那么MS SqlServer思想肯定也是一样，那么socket的接收byte数据要转化为String，那肯定要使用
如下方法：
//String

public String(byte bytes[], Charset charset) {
    this(bytes, 0, bytes.length, charset);
}

如果没有配置编码，则使用如方法：

public String(byte bytes[]) {
    this(bytes, 0, bytes.length);
}

public String(byte bytes[], int offset, int length) {
    checkBounds(bytes, offset, length);
    //委托给StringCoding解码
    this.value = StringCoding.decode(bytes, offset, length);
}

//StringCoding

static char[] decode(byte[] ba, int off, int len) {
    //关键在这句获取系统默认字符编码
    String csn = Charset.defaultCharset().name();
    try {
        // use charset name decode() variant which provides caching.
        return decode(csn, ba, off, len);
    } catch (UnsupportedEncodingException x) {
        warnUnsupportedCharset(csn);
    }
    try {
        return decode("ISO-8859-1", ba, off, len);
    } catch (UnsupportedEncodingException x) {
        // If this code is hit during VM initialization, MessageUtils is
        // the only way we will be able to get any kind of error message.
        MessageUtils.err("ISO-8859-1 charset not available: "
                         + x.toString());
        // If we can not find ISO-8859-1 (a required encoding) then things
        // are seriously wrong with the installation.
        System.exit(1);
        return null;
    }
}
public static Charset defaultCharset() {
    if (defaultCharset == null) {
        synchronized (Charset.class) {
	    //在当前线程访问控制权限下，获取系统文件编码
            String csn = AccessController.doPrivileged(
                new GetPropertyAction("file.encoding"));
            Charset cs = lookup(csn);
            if (cs != null)
                defaultCharset = cs;
            else
	       //如果系统编码为空，则默认为UTF-8
                defaultCharset = forName("UTF-8");
        }
    }
    return defaultCharset;
}

猜想是不是系统编码导致的呢？linux系统的编码为UTF-8

donald@linux:~/tomcat/bin>locale
...
LC_ALL=zh_CN.UTF-8
LANG=zh_CN.UTF-8  

修改系统编码为GBK，修改/etc/profile，添加如下两行：

export LC_ALL=zh_CN.G
export LANG=zh_CN.GBK

donald@linux:~/tomcat/bin>source /etc/profile
donald@linux:~/tomcat/bin> tail -n 20 /etc/profile
...
export LC_ALL=zh_CN.GBK  
export LANG=zh_CN.GBK  
donald@linux:~/tomcat/bin> 

重新启动应用，测试，it is ok， feel good...

如果不是这个原因可以尝试从结果结果集中先获取数据，再将数据转换为GBK编码格式：

String oname=rs.getString("name");
byte[] namebyte=oname.getBytes("GBK2312");
name=new String(namebyte);

这种方法理论上没有任何问题，我没有测试，如果上面方法不行，可以尝试用这种方法。