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POMybatis Custom Type handler: call FileInputStream.close() after query being executed
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  1. POMybatis Custom Type handler: call FileInputStream.close() after query being executed
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    copied!<p>I am trying to implement MyBatis custom type handler for File using FileInputStream.</p> <p>here is my code for setting:</p> <pre><code>@MappedJdbcTypes(JdbcType.LONGVARBINARY) public class FileByteaHandler extends BaseTypeHandler&lt;File&gt; { @Override public void setNonNullParameter(PreparedStatement ps, int i, File file, JdbcType jdbcType) throws SQLException{ try { FileInputStream fis = new FileInputStream(file); ps.setBinaryStream(1, fis, (int) file.length()); } catch(FileNotFoundException ex) { Logger.getLogger(FileByteaHandler.class.getName()).log(Level.SEVERE, null, ex); } } </code></pre> <p>}</p> <p>My question is:</p> <p>I can not close this FileInputStream at the end of this method, otherwise MyBatis will not be able to read the data from it. In fact, I do not know where I can close the FileInputStream. Is there a way to call close() after the query being excuted in MyBatis.</p> <p>Thanks in advance,</p> <p><strong>UPDATE</strong></p> <p>Thanks for Jarandinor's help. Here is my code for this type handler. and hopefully it can help someone:</p> <pre><code>@MappedJdbcTypes(JdbcType.LONGVARBINARY) public class FileByteaHandler extends BaseTypeHandler&lt;File&gt; { @Override public void setNonNullParameter(PreparedStatement ps, int i, File file, JdbcType jdbcType) throws SQLException { try { AutoCloseFileInputStream fis = new AutoCloseFileInputStream(file); ps.setBinaryStream(1, fis, (int) file.length()); } catch(FileNotFoundException ex) { Logger.getLogger(FileByteaHandler.class.getName()).log(Level.SEVERE, null, ex); } } @Override public File getNullableResult(ResultSet rs, String columnName) throws SQLException { File file = null; try(InputStream input = rs.getBinaryStream(columnName)) { file = getResult(rs, input); } catch(IOException e) { System.out.println(e.getMessage()); } return file; } public File creaetFile() { File file = new File("e:/target-file"); //your temp file path return file; } private File getResult(ResultSet rs, InputStream input) throws SQLException { File file = creaetFile(); try(OutputStream output = new FileOutputStream(file)) { int bufSize = 0x8000000; byte buf[] = new byte[bufSize]; int s = 0; int tl = 0; while( (s = input.read(buf, 0, bufSize)) &gt; 0 ) { output.write(buf, 0, s); tl += s; } output.flush(); } catch(IOException e) { System.out.println(e.getMessage()); } return file; } @Override public File getNullableResult(ResultSet rs, int columnIndex) throws SQLException { File file = null; try(InputStream input = rs.getBinaryStream(columnIndex)) { file = getResult(rs, input); } catch(IOException e) { System.out.println(e.getMessage()); } return file; } @Override public File getNullableResult(CallableStatement cs, int columnIndex) throws SQLException { throw new SQLException("getNullableResult(CallableStatement cs, int columnIndex) is called"); } private class AutoCloseFileInputStream extends FileInputStream { public AutoCloseFileInputStream(File file) throws FileNotFoundException { super(file); } @Override public int read() throws IOException { int c = super.read(); if(available() &lt;= 0) { close(); } return c; } public int read(byte[] b) throws IOException { int c = super.read(b); if(available() &lt;= 0) { close(); } return c; } public int read(byte[] b, int off, int len) throws IOException { int c = super.read(b, off, len); if(available() &lt;= 0) { close(); } return c; } } } public AutoCloseFileInputStream(File file) throws FileNotFoundException { super(file); } @Override public int read() throws IOException { int c = super.read(); if( c == -1 ) { close(); } return c; } public int read(byte[] b) throws IOException { int c = super.read(b); if( c == -1 ) { close(); } return c; } public int read(byte[] b, int off, int len) throws IOException { int c = super.read(b, off, len); if(available() &lt;= 0) { close(); } return c; } } </code></pre>
 

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