无法将图像保存为blob到sqlite

Question

我正在使用SQLite，我无法将图像保存到数据库。 这是我的代码：

File file = new File(url); 
    try { 
    fis = new FileInputStream(file); 
    } catch (FileNotFoundException e) {} 
fileLenght = (int) file.length(); 

stat.executeUpdate("create table "+tableName+" (id int,name String ,image Blob, features String);"); 
prep = conn.prepareStatement("insert into "+tableName+" values (?, ?, ?, ?);"); 
prep.setBinaryStream(3, fis, fileLenght); 

这是我收到的错误：

java.sql.SQLException: not implemented by SQLite JDBC driver 
    at org.sqlite.Unused.unused(Unused.java:29) 
    at org.sqlite.Unused.setBinaryStream(Unused.java:58) 

我使用下面的jar：sqlitejdbc-v056.jar。

任何想法？ 谢谢

Answer 1

您正在使用的SQLite JDBC实现未实现setBinaryStream（因此，准确的未由SQLite JDBC驱动程序错误消息实现）。

您需要改用setBytes方法。

Answer 2

看起来你没有绑定到你的语句中的所有四个参数。

Answer 3

你可以很容易地插入一个图像到数据库中说SQLite看到我的下面的代码。 我没有使用DBase连接的属性文件，你可以放在任何地方。

public class JDBCSqliteConn 
{ 
    public static void main(String args[]) throws FileNotFoundException, IOException 
    { 
     Connection connection = null; 
     //ResultSet resultSet = null; 
     PreparedStatement ps = null; 
     String file = "C:\\Fingerprint\\histoImg_med.png"; 
     Properties prop = new Properties(); 
     int s = 0; 
     byte[] person_image = null; 
     File image = new File(file); 
     FileInputStream fis = new FileInputStream(image); 
     ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
     byte[] buf = new byte[1024]; 

     try { 
      for (int readNum; (readNum = fis.read(buf)) != -1;) 
      { 
       bos.write(buf, 0, readNum); 
       //no doubt here is 0 
       /*Writes len bytes from the specified byte array starting at offset 
       off to this byte array output stream.*/ 
       System.out.println("read " + readNum + " bytes,"); 
      } 
     } catch (IOException ex) { 
      System.err.println(ex.getMessage()); 
     } 
     person_image = bos.toByteArray(); 

     try { 
      prop.load(new FileInputStream("C:\\dbconfig.properties")); 
      Class.forName(prop.getProperty("driver")); 
      connection = DriverManager.getConnection(prop.getProperty("url")); 

      ps = connection.prepareStatement("INSERT INTO epmc_tbl_test_img (hhld_photo) VALUES (?)"); 
      ps.setBytes(1, person_image); 
      s = ps.executeUpdate(); 
      if (s > 0) 
      { 
       System.out.println("Image Uploaded"); 
      } 
      ps.close(); 
     } catch (Exception e) { 
      e.printStackTrace(); 
     } finally { 
      try { 
       ps.close(); 
       connection.close(); 
      } catch (Exception e) { 
       e.printStackTrace(); 
      } 
     } 
    } 
} 

背后的逻辑为Am转换图像以字节组，然后存储到数据库时，SQLite接受图像类型BLOB字节数组

这里是我dbconfig.properties文件

driver = org.sqlite.JDBC 
url = jdbc:sqlite:C:\\Ronald\\Personal\\epmc\\JavaJ2EE\\EPMC.db 

尝试使用此代码。

Answer 4

已将submitted修复为包含setBinaryStream实现的Xerial。

使用setBytes不是我的选择，因为我使用hibernate来访问数据库。

diff -r 144ade82d1fe -r 5a141e1b82f0 src/main/java/org/sqlite/PrepStmt.java 
--- a/src/main/java/org/sqlite/PrepStmt.java  Thu Jun 09 17:15:36 2011 +0900 
+++ b/src/main/java/org/sqlite/PrepStmt.java  Wed Oct 26 11:02:15 2011 -0700 
@@ -16,7 +16,9 @@ 

package org.sqlite; 

+import java.io.ByteArrayOutputStream; 
import java.io.IOException; 
+import java.io.InputStream; 
import java.io.Reader; 
import java.sql.Date; 
import java.sql.ParameterMetaData; 
@@ -254,6 +256,38 @@ 
     batch(pos, value); 
    } 

+ @Override 
+ public void setBinaryStream(int pos, InputStream istream, int length) throws SQLException 
+ { 
+  ByteArrayOutputStream baos = new ByteArrayOutputStream(); 
+  try 
+  { 
+  int bval = 0; 
+ 
+  while ((bval = istream.read()) != -1) 
+  { 
+   baos.write(bval); 
+  } 
+  baos.flush(); 
+  setBytes(pos, baos.toByteArray()); 
+  } 
+  catch (IOException e) 
+  { 
+  throw new SQLException("Cannot read from binary stream, exception message: " + e.getMessage()); 
+  } 
+  finally 
+  { 
+  try 
+  { 
+   baos.close(); 
+  } 
+  catch (IOException e) 
+  { 
+   throw new SQLException("Can't close stream"); 
+  } 
+  } 
+ } 
+ 
    public void setCharacterStream(int pos, Reader reader, int length) throws SQLException { 
     try { 
      // copy chars from reader to StringBuffer 

Answer 5

要使用Hibernate使用它，你必须使用正确的用户类型：

public class PersistentFileAsBlob implements EnhancedUserType, Serializable { 

    public static final PersistentFileAsBlob INSTANCE = new PersistentFileAsBlob(); 

    private static final int[] SQL_TYPES = new int[] { Types.BLOB }; 

    @Override 
    public int[] sqlTypes() { 
     return SQL_TYPES; 
    } 

    @Override 
    public Class<?> returnedClass() { 
     return File.class; 
    } 

    @Override 
    public boolean equals(Object x, Object y) throws HibernateException { 
     if (x == y) { 
      return true; 
     } 
     if (x == null || y == null) { 
      return false; 
     } 
     File dtx = (File) x; 
     File dty = (File) y; 
     return dtx.equals(dty); 
    } 

    @Override 
    public int hashCode(Object x) throws HibernateException { 
     return x.hashCode(); 
    } 

    @Override 
    public Object nullSafeGet(ResultSet rs, String[] names, Object owner) 
      throws HibernateException, SQLException { 
     if (owner == null) { 
      return null; 
     } 

     FileOutputStream fos = null; 
     GzipCompressorInputStream cis = null; 
     try { 
      File file = File.createTempFile(String.valueOf(owner.hashCode()), 
        ""); 
      byte[] bytes = rs.getBytes(names[0]); 
      System.out.println(bytes.length); 
      fos = new FileOutputStream(file); 
      cis = new GzipCompressorInputStream(new BufferedInputStream(
        new ByteArrayInputStream(bytes))); 
      int n = 0; 
      final byte[] buffer = new byte[1024]; 
      while (-1 != (n = cis.read(buffer))) { 
       fos.write(buffer, 0, n); 
      } 
      fos.close(); 
      return file; 
     } catch (Exception e) { 
      e.printStackTrace(); 
      throw new RuntimeException(e); 
     } finally { 
      if (fos != null) 
       try { 
        fos.close(); 
       } catch (IOException e) { 
        throw new RuntimeException(e); 
       } 
      if (cis != null) 
       try { 
        cis.close(); 
       } catch (IOException e) { 
        throw new RuntimeException(e); 
       } 
     } 
    } 

    @Override 
    public void nullSafeSet(PreparedStatement st, Object value, int index) 
      throws HibernateException, SQLException { 
     if (value == null) { 
      StandardBasicTypes.BINARY.nullSafeSet(st, null, index); 
      return; 
     } 

     File file = (File) value; 

     FileInputStream fis = null; 
     ByteArrayOutputStream bos = null; 
     GzipCompressorOutputStream cos = null; 
     try { 
      fis = new FileInputStream(file); 
      bos = new ByteArrayOutputStream(); 
      cos = new GzipCompressorOutputStream(new BufferedOutputStream(bos)); 
      int n = 0; 
      final byte[] buffer = new byte[1024]; 
      while (-1 != (n = fis.read(buffer))) { 
       cos.write(buffer, 0, n); 
      } 
      cos.close(); 
      StandardBasicTypes.BINARY.nullSafeSet(st, bos.toByteArray(), index); 
     } catch (Exception e) { 
      e.printStackTrace(); 
      throw new RuntimeException(e); 
     } finally { 
      if (fis != null) 
       try { 
        fis.close(); 
       } catch (IOException e) { 
        throw new RuntimeException(e); 
       } 
      if (cos != null) 
       try { 
        cos.close(); 
       } catch (IOException e) { 
        throw new RuntimeException(e); 
       } 
     } 
    } 

    @Override 
    public Object deepCopy(Object value) throws HibernateException { 
     return value; 
    } 

    @Override 
    public boolean isMutable() { 
     return false; 
    } 

    @Override 
    public Serializable disassemble(Object value) throws HibernateException { 
     return (Serializable) value; 
    } 

    @Override 
    public Object assemble(Serializable cached, Object owner) 
      throws HibernateException { 
     return cached; 
    } 

    @Override 
    public Object replace(Object original, Object target, Object owner) 
      throws HibernateException { 
     return original; 
    } 

    @Override 
    public String objectToSQLString(Object value) { 
     throw new UnsupportedOperationException(); 
    } 

    @Override 
    public String toXMLString(Object value) { 
     return value.toString(); 
    } 

    @Override 
    public Object fromXMLString(String xmlValue) { 
     return new File(xmlValue); 
    } 

} 

然后你注释您键入，参照本用户类型：

@Entity 
public class Mensagem { 

    @Column(nullable = false) 
    @Type(type = "package.to.class.PersistentFileAsBlob") 
    private File file; 

} 

正如你可以看到我m在检索前保存和解压缩之前压缩数据。看看this site。