java多线程，将oracle中数据导入到sql到文件（包括大字段转换成字符串）

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Reader;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;

import oracle.sql.CLOB;

public class OracleTest extends Thread{

private int startIndex = 0;
private String tableName;
private static int fetchCount = 100000;

public OracleTest(int startIndex, String tableName) {
this.startIndex = startIndex;
this.tableName = tableName;
}

public static void main(String[] args) {
try {
// 第一步要Jar包:在oracle安装的目录下,盘符:\oracle\ora92\jdbc\lib\ojdbc14.jar
// 加载驱动
Class.forName("oracle.jdbc.driver.OracleDriver");

// 连接字符串(协议名:jdbc,子协议名: oracle:thin 子名称:@localhost:1521:oracleDB)
// String url ="jdbc:oracle:thin:@localhost:1521:ora";

String tableNameString= "table_name";

int count = getCount(tableNameString);

int fetchTimes = count % fetchCount == 0 ? count/fetchCount : (count/fetchCount + 1);
for (int i=0; i<fetchTimes; i++) {
OracleTest o = new OracleTest(i, tableNameString);
o.start();
}

} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}

@Override
public void run() {
int startRow = startIndex * fetchCount;
int endRow = (startIndex+1)* fetchCount;
System.out.println(Thread.currentThread().getName() +", "
+ startIndex + "," + startRow + "," + endRow+ ", start");
createInsertSQL(tableName, startRow, endRow);
System.out.println(Thread.currentThread().getName() +", "
+ startIndex + "," + startRow + "," + endRow+ ", END");
}

private void createInsertSQL(String tableName, int startRow, int endRow) {
String url = "jdbc:oracle:thin:@localhost:1521:oral";
Connection conn = null;
Statement st = null;
ResultSet rs = null;
try {
// 建立连接
conn = DriverManager.getConnection(url, "username", "password");

// 创建Statement或者是PreparedStatement语句
st = conn.createStatement();
String sqlStr = "select * from (select t1.*,rownum as rn from " + tableName + " t1 where rownum<=" + endRow +") t2 where t2.rn>" + startRow;
// System.out.println(sqlStr);

// 执行查询
rs = st.executeQuery(sqlStr);
ResultSetMetaData data = rs.getMetaData();

BufferedWriter writer = null;
FileWriter fileWriter = null;
try {
fileWriter = new FileWriter(new File("/Users/cxt/red/tmp/" + tableName +  "_" + (startRow/fetchCount) + ".sql"));
writer = new BufferedWriter(fileWriter);

String sql = "INSERT INTO " + tableName;
while (rs.next()) {
StringBuffer columnBuffer = new StringBuffer("(");
StringBuffer valueBuffer = new StringBuffer("VALUES(");
for (int i = 1; i <= data.getColumnCount(); i++) {
// 获得指定列的列名
String columnName = data.getColumnName(i);

// 获得指定列的数据类型名
String columnTypeName = data.getColumnTypeName(i);

// 获得指定列的列值
String columnValue = null;
if(columnTypeName.contains("CLOB")) {
columnValue = clobToString((oracle.sql.CLOB) rs.getClob(i));
} else {
columnValue = rs.getString(i);
}

if (columnTypeName.contains("DATE")) {
if (columnValue.endsWith(".0")) {
columnValue = columnValue.substring(0,
columnValue.length() - 2);
}
}
if ("null".equals(columnValue)) {
columnValue = null;
}

columnBuffer.append(columnName).append(",");
if (!columnTypeName.contains("NUMBER")
&& null != columnValue) {
valueBuffer.append("'").append(columnValue)
.append("'");
} else {
valueBuffer.append(columnValue);
}
valueBuffer.append(",");
}
String column = columnBuffer.toString();
column = column.substring(0, column.length() - 1) + ")";

String value = valueBuffer.toString();
value = value.substring(0, value.length() - 1) + ");";

String sqlString = sql + column + value;
// System.out.println(Thread.currentThread().getName()+"; "+sqlString);
writer.write(sqlString + "\r\n");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {

writer.close();
fileWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}

// while (rs.next()) {
// for (int i = 1; i <= data.getColumnCount(); i++) {
// // 获得所有列的数目及实际列数
// int columnCount = data.getColumnCount();
// // 获得指定列的列名
// String columnName = data.getColumnName(i);
// // 获得指定列的列值
// String columnValue = rs.getString(i);
// // 获得指定列的数据类型
// int columnType = data.getColumnType(i);
// // 获得指定列的数据类型名
// String columnTypeName = data.getColumnTypeName(i);
// // 所在的Catalog名字
// String catalogName = data.getCatalogName(i);
// // 对应数据类型的类
// String columnClassName = data.getColumnClassName(i);
// // 在数据库中类型的最大字符个数
// int columnDisplaySize = data.getColumnDisplaySize(i);
// // 默认的列的标题
// String columnLabel = data.getColumnLabel(i);
// // 获得列的模式
// String schemaName = data.getSchemaName(i);
// // 某列类型的精确度(类型的长度)
// int precision = data.getPrecision(i);
// // 小数点后的位数
// int scale = data.getScale(i);
// // 获取某列对应的表名
// String tableName = data.getTableName(i);
// // 是否自动递增
// boolean isAutoInctement = data.isAutoIncrement(i);
// // 在数据库中是否为货币型
// boolean isCurrency = data.isCurrency(i);
// // 是否为空
// int isNullable = data.isNullable(i);
// // 是否为只读
// boolean isReadOnly = data.isReadOnly(i);
// // 能否出现在where中
// boolean isSearchable = data.isSearchable(i);
// System.out.println(columnCount);
// System.out.println("获得列" + i + "的字段名称:" + columnName);
// System.out.println("获得列" + i + "的字段值:" + columnValue);
// System.out.println("获得列" + i + "的类型,返回SqlType中的编号:"
// + columnType);
// System.out.println("获得列" + i + "的数据类型名:" + columnTypeName);
// System.out.println("获得列" + i + "所在的Catalog名字:"
// + catalogName);
// System.out.println("获得列" + i + "对应数据类型的类:"
// + columnClassName);
// System.out.println("获得列" + i + "在数据库中类型的最大字符个数:"
// + columnDisplaySize);
// System.out.println("获得列" + i + "的默认的列的标题:" + columnLabel);
// System.out.println("获得列" + i + "的模式:" + schemaName);
// System.out
// .println("获得列" + i + "类型的精确度(类型的长度):" + precision);
// System.out.println("获得列" + i + "小数点后的位数:" + scale);
// System.out.println("获得列" + i + "对应的表名:" + tableName);
// System.out.println("获得列" + i + "是否自动递增:" + isAutoInctement);
// System.out.println("获得列" + i + "在数据库中是否为货币型:" + isCurrency);
// System.out.println("获得列" + i + "是否为空:" + isNullable);
// System.out.println("获得列" + i + "是否为只读:" + isReadOnly);
// System.out.println("获得列" + i + "能否出现在where中:"
// + isSearchable);
// }
// }
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
rs.close();
st.close();
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

private static int getCount(String tableName) {
String url = "jdbc:oracle:thin:@10.27.4.121:1521:ora10g";
Connection conn = null;
Statement st = null;
ResultSet rs = null;
try {
// 建立连接
conn = DriverManager.getConnection(url, "newpowersite", "newpowersite_xunjie123");

// 创建Statement或者是PreparedStatement语句
st = conn.createStatement();
String sqlStr = "select count(0) from " + tableName;

// 执行查询
rs = st.executeQuery(sqlStr);
rs.next();
return rs.getInt(1);
} catch (Exception ex) {
ex.printStackTrace();
} finally {
try {
rs.close();
st.close();
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return 0;
}

// 将字CLOB转成STRING类型
private String clobToString(CLOB clob) throws SQLException, IOException {

String reString = "";
if(null == clob) {
return null;
}
Reader is = clob.getCharacterStream();// 得到流
BufferedReader br = new BufferedReader(is);
String s = br.readLine();
StringBuffer sb = new StringBuffer();
while (s != null) {// 执行循环将字符串全部取出付值给StringBuffer由StringBuffer转成STRING
sb.append(s);
s = br.readLine();
}
reString = sb.toString();
return reString;
}
}

上面代码存在的几个问题，以及需要注意的事项：

1、上面代码没有对字符串中的特殊字符进行处理，比如单引号('); 包括对于已经转义的不处理，未转义的要转义

2、上面代码中生成文件的最后是以逗号(,)结尾的，需要替换成分号(;)

3、生成的那件结尾如果包含^M换行符的话，需要处理掉，否则入库会又乱码。