连接到数据库:
public DBSource(ConnectionInfo ci) throws
ClassNotFoundException, InstantiationException,
IllegalAccessException, SQLException
{
Class.forName("com.mysql.jdbc.Driver").newInstance();
String dbPath = String.format(
"jdbc:mysql://%s:%d/%s?user=%s&password=%s&characterEncoding=utf-8&" +
"useUnicode=true", ci.host, ci.port, ci.dbName, ci.user, ci.password);
conn = java.sql.DriverManager.getConnection(dbPath);
prepareTables();
}
建表代码:
private void prepareTables() throws SQLException
{
java.sql.Statement stat = conn.createStatement();
String query = "set names utf8";
stat.execute(query);
query = "set character set utf8";
stat.execute(query);
query = "show variables like '%char%'";
stat.execute(query);
java.sql.ResultSet rs = stat.getResultSet();
while (rs.next())
{
String k = rs.getString(1);
String v = rs.getString(2);
System.out.println(k + " - " + v);
}
query = "drop table if exists clt";
stat.execute(query);
query = "create table clt"
+ "("
+ " id bigint not null"
+ ", text varchar(50) not null"
+ ") default character set utf8";
stat.execute(query);
}
行插入:
public void visit(Insert i) throws SQLException
{
String query = "insert into clt"
+ " (id, text) values (?, ?)";
java.sql.PreparedStatement stmt = conn.prepareStatement(query);
if (i.rowData.id == 12656697)
{
String toOut = "<<< " + Long.toString(i.rowData.id) + " - " + i.rowData.text;
System.out.println(toOut);
}
int it = 0;
stmt.setLong(++it, i.rowData.id);
stmt.setString(++it, i.rowData.text);
stmt.execute();
stmt.close();
}
检查数据:
public void checkText() throws SQLException
{
java.sql.Statement stmt = conn.createStatement();
String query = "select id, text from clt where id = '12656697'";
stmt.execute(query);
java.sql.ResultSet rs = stmt.getResultSet();
while (rs.next())
{
String k = rs.getString(1);
String v = rs.getString(2);
String toOut = ">>> " + k + " - " + v;
System.out.println(toOut);
}
}
output:
character_set_client - utf8
character_set_connection - latin1
character_set_database - latin1
character_set_filesystem - binary
character_set_results - utf8
character_set_server - utf8
character_set_system - utf8
character_sets_dir - /usr/share/mysql/charsets/
<<< 12656697 - Апарати
>>> 12656697 - ???????
Problem:在表中我有“??????????” 文本字段中的符号。
预期的字符串是: Апарати
result: ???????
它是某种magic?
我解决了一个问题...但如果有人可以向我解释,我仍然会感激。
So.
- 我添加到了 Costis Aivalis 建议的 /etc/mysql/my.cnf 行中
结果相同
- 我从代码中删除了几行:
query = "设置字符集utf8";
stat.execute(查询);
这是工作!!! :)