Java大数据
大数据(像数据库中插入图片)
import java.sql.SQLException; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.FileDialog; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.SWT; import org.eclipse.swt.widgets.Text; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent;
public class TestPIC {
protected Shell shell;
private Text text;
/**
* Launch the application.
* @param args
*/
public static void main(String[] args) {
try {
TestPIC window = new TestPIC();
window.open();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Open the window.
*/
public void open() {
Display display = Display.getDefault();
createContents();
shell.open();
shell.layout();
while (!shell.isDisposed()) {
if (!display.readAndDispatch()) {
display.sleep();
}
}
}
/**
* Create contents of the window.
*/
protected void createContents() {
shell = new Shell();
shell.setSize(450, 300);
shell.setText("SWT Application");
Label label = new Label(shell, SWT.NONE);
label.setBounds(20, 95, 61, 17);
label.setText("头像");
text = new Text(shell, SWT.BORDER);
text.setBounds(113, 95, 192, 23);
Button button = new Button(shell, SWT.NONE);
button.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent e) {
FileDialog dialog = new FileDialog(shell,SWT.OPEN);
String basepath=System.getProperty("user.home");//设置 初始路径
dialog.setFilterPath(basepath);
dialog.setFilterExtensions(new String[]{"*.jpg","*.jpeg","*.png"}); //它使用指定的扩展名集合进行过滤
String fileName = dialog.open();
if(fileName==null||"".equals(fileName)){
return;
}
text.setText(fileName);
}
});
button.setBounds(344, 91, 80, 27);
button.setText("浏览");
Button button_1 = new Button(shell, SWT.NONE);
button_1.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent e) {
String picpath=text.getText().trim();
PicBiz pb=new PicBiz();
try {
pb.savePic(picpath);
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
});
button_1.setBounds(168, 156, 80, 27);
button_1.setText("保存");
}} import java.io.BufferedInputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.UUID;
import com.yc.dao.dbhelper;
public class PicBiz { public void savePic(String picpath) throws SQLException { String picid=UUID.randomUUID().toString(); dbhelper db= new dbhelper(); String sql=”insert into pic values(?,empty_blob())”;
String sql2="select pic from pic where picid=? for update";//for update 锁定这一行数据
Connection con=null;
try {
con=db.getCon();
con.setAutoCommit(false);//关闭隐式提交
PreparedStatement pstmt=con.prepareStatement(sql);//创建语句对象 ，发给数据库执行
pstmt.setString(1, picid);//设置参数
pstmt.execute();//数据库执行语句
pstmt=con.prepareStatement(sql2);
pstmt.setString(1, picid);
pstmt.execute();
ResultSet rs=pstmt.executeQuery(); //得到数据库中语句执行的结果集
if(rs!=null&&rs.next()){
OutputStream oos=null;//像数据库表中输出图片
InputStream iis=null;//从本地读文件
oracle.sql.BLOB b= (oracle.sql.BLOB) rs.getBlob(1);//取出图片所在位置
iis=new BufferedInputStream(new FileInputStream(new File (picpath)));//通过输入流读取图片数据
oos=b.getBinaryOutputStream();//从结果集中取出输入流 用于向数据库写数据
byte[] bs=new byte[1024];
int length=-1;
while(( length=iis.read(bs,0,bs.length))!=-1){
oos.write(bs,0,length);
oos.flush();
}
con.commit();
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
con.rollback();
} finally{
con.setAutoCommit(true);
}
}