深入浅出JDBC-操作时间与大对象(Clob/Blob)

一、时间(Date、Time、Timestamp)

public class TimeData {
PreparedStatement pStatement=null;
//操作日期类型的数据
public void insertDate(Connection connection,long time){
try {
String sql="insert into user(regTime)values(?)";
pStatement=connection.prepareStatement(sql);
//插入的时间为当前日期
pStatement.setDate(1,new Date(time));
pStatement.executeUpdate();
}catch (Exception e){
e.printStackTrace();
}finally {
DBUtil.getInstance().close(pStatement);
DBUtil.getInstance().close(connection);
}
}

//操作时间类型的数据
public void insertTimestamp(Connection connection,long time){
try {
String sql="insert into user(loginTime)values(?)";
pStatement=connection.prepareStatement(sql);
java.sql.Timestamp timestamp=new java.sql.Timestamp(time);
//插入的时间为当前时间
pStatement.setTimestamp(1,timestamp);
pStatement.executeUpdate();
}catch (Exception e){
e.printStackTrace();
}finally {
DBUtil.getInstance().close(pStatement);
DBUtil.getInstance().close(connection);
}
}

/**
*批量添加某一区间的数据
* @param connection
* @param first 注册时间
* @param seconed  登录时间
* @param rowNum 添加的记录的条数
*/
public void insertBatch(Connection connection,long first,long seconed,int rowNum){
try {
String sql="insert into user(regTime,loginTime) values(?,?)";
pStatement=connection.prepareStatement(sql);
for(int i=0;i<rowNum;i++){
long regTime=new Random().nextInt(100000000)+first;
long loginTime=seconed-new Random().nextInt(10000000);
pStatement.setDate(1,new java.sql.Date(regTime));
pStatement.setTimestamp(2,new Timestamp(loginTime));
pStatement.executeUpdate();
}
}catch (Exception e){
e.printStackTrace();
}finally {
DBUtil.getInstance().close(pStatement);
DBUtil.getInstance().close(connection);
}
}

//插入指定时间的数据
public long StringToDate(String dateString){
try {
SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
return sdf.parse(dateString).getTime();
} catch (ParseException e) {
e.printStackTrace();
}
return 0;
}

//查询日期、时间
public void query(Connection connection){
Statement statement=null;
ResultSet rs=null;
try {
statement=connection.createStatement();
String sql="select regTime,loginTime from user";
statement.executeQuery(sql);
rs=statement.executeQuery(sql);
while(rs.next()){
Date date=rs.getDate("regTime");
Timestamp ts=rs.getTimestamp("loginTime");
System.out.println(date+"-----"+ts);
}
} catch (SQLException e) {
e.printStackTrace();
}
}

}

二、时间单元测试

public class TestTimeData {

Connection connection=DBUtil.getInstance().getConnection();
TimeData timeData=new TimeData();

@Test
public void insertDate(){
timeData.insertDate(connection,System.currentTimeMillis());
}

@Test
public void insertTimestamp(){
timeData.insertTimestamp(connection,System.currentTimeMillis());
}

@Test
public void insertAppointedDate(){
//插入指定时间
long t=timeData.StringToDate("2017-01-01 15:30:00");
timeData.insertDate(connection,t);
}

@Test
public void insertBatchDate(){
//批量插入某一时间段时间
long start=timeData.StringToDate("2016-01-01 12:50:20");
long end=timeData.StringToDate("2017-12-30 02:00:00");
timeData.insertBatch(connection,start,end,50);
}

@Test
public void query(){
timeData.query(connection);
}
}

三、大数据对象(Clob、Blob)

public class BigData{
PreparedStatement pStatement=null;
/**
* 插入海量文字通过读取本地文件
* @param filePath 文件的物理路径
* @param connection
*/
public void insertClobByReadFile(Connection connection,String filePath )   {
try {
String sql="insert into user(resume)values(?)";
pStatement=connection.prepareStatement(sql);
pStatement.setClob(1,new FileReader(new File(filePath)));
pStatement.executeUpdate();
}catch (Exception e){
e.printStackTrace();
}finally {
DBUtil.getInstance().close(pStatement);
DBUtil.getInstance().close(connection);
}
}

/**
* 读取存储在数据库的海量文字文件
*/
public void queryClob(Connection connection,int id) {
ResultSet rs=null;
try {
String sql="select resume from user where id=?";
pStatement=connection.prepareStatement(sql);
pStatement.setInt(1,id);
rs=pStatement.executeQuery();
while (rs.next()){
Clob clob=rs.getClob("resume");
Reader r=clob.getCharacterStream();
int temp=0;
while((temp=r.read())!=-1){
System.out.print((char)temp);
}
}
}catch (Exception e){
e.printStackTrace();
}finally {
DBUtil.getInstance().close(rs);
DBUtil.getInstance().close(pStatement);
DBUtil.getInstance().close(connection);
}

}

/**
* 存储图片文件
* @param connection
* @param imgPath 图片的物理路径
*/
public void insertBlob(Connection connection,String imgPath) {
try {
pStatement=connection.prepareStatement("insert into user(headImg) values(?);");
//获得图片的输入流
pStatement.setBlob(1,new FileInputStream(new File(imgPath)));
pStatement.execute();
}catch (Exception e){
e.printStackTrace();
}finally {
DBUtil.getInstance().close(pStatement);
DBUtil.getInstance().close(connection);
}
}

/**
*  获取图片文件，并且输入到本地：F:/hello.jpg。
* @param connection
* @param id
*/
public void queryBlob(Connection connection,int id){
ResultSet rs;
try {
String sql="select headImg from user where id=?";
pStatement=connection.prepareStatement(sql);
pStatement.setInt(1,id);
rs=pStatement.executeQuery();
while(rs.next()){
//获得文件的blob对象
Blob blob=rs.getBlob("headImg");
//获取文件的输入流
InputStream is=blob.getBinaryStream();
//建立输出流用于输入图片查看结果
OutputStream os=new FileOutputStream(new File("F:/hello.txt"));
int temp=0;
while((temp=is.read())!=-1){
os.write(temp);
}
os.flush();
os.close();
}

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

}

}

大数据对象单元测试

public class TestBigData {
　　//获取数据库连接
Connection connection=DBUtil.getInstance().getConnection();
BigData bigData=new BigData();
@Test
public void insertClob(){
try {
String filePath="F:/testclob.txt";
bigData.insertClobByReadFile(connection,filePath);
} catch (Exception e) {
e.printStackTrace();
}
}

@Test
public void queryClob(){
try {
bigData.queryClob(connection,1);
} catch (Exception e) {
e.printStackTrace();
}finally {
DBUtil.getInstance().close(connection);
}
}

@Test
public void insertBlob(){
String imgPath="F:/testclob.txt";
bigData.insertBlob(connection,imgPath);
}

@Test
public void queryBlob(){
bigData.queryBlob(connection,15906);
}
}