我有一个22.0
的文件，我必须将它作为Clob保存在我的实体中。
如何将byte[]保存为byte[]？
答案 0 :(得分：1)
要从Oracle上的Clob获取byte[]，您可以
private Clob createClob(byte[] data, Connection conn) {
CLOB clob = null;
try {
clob = CLOB.createTemporary(conn, false, oracle.sql.CLOB.DURATION_SESSION);
clob.open(CLOB.MODE_READWRITE);
OutputStream out = (OutputStream) clob.setAsciiStream(0L);
out.write(data);
out.flush();
out.close();
}
catch (Exception e) {
logger.error("", e);
}
finally {
try {
if (clob != null && clob.isOpen()) clob.close();
}
catch (SQLException e) {
logger.error("Unable to close CLOB", e);
}
}
return clob;
}
创建一个Blob（二进制）几乎是一样的，只需用 blob 和OutputStream out = (OutputStream) blob.setBinaryStream(0L);替换 clob
答案 1 :(得分：0)
使用Apache commons-io
byte[] data = IOUtils.toByteArray(clob.getAsciiStream());
如果您需要特殊编码或遇到问题，请尝试：
byte[] data = IOUtils.toByteArray(clob.getCharacterStream(), "UTF-8");
答案 2 :(得分：0)
import android.content.ContentProvider;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.AbstractWindowedCursor;
import android.database.Cursor;
import android.database.CursorWindow;
import android.database.CursorWrapper;
import android.database.MatrixCursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.media.ExifInterface;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v4.content.CursorLoader;
import android.util.Log;
import java.io.IOException;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.List;
public class PhotoProvider extends ContentProvider {
// The URI Matcher used by this content provider.
private static final UriMatcher sUriMatcher = buildUriMatcher();
static final int PHOTO = 100;
static final int PHOTO_COMMENT = 101;
static final int PHOTO_AUTHOR = 102;
static UriMatcher buildUriMatcher() {
final UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);
final String authority = PhotoContract.CONTENT_AUTHORITY;
// matches photo/<any number> meaning any photo ID
matcher.addURI(authority, PhotoContract.PATH_PHOTO + "/#", PHOTO);
// matches photo/<photo id>/comment/ (comment text in ContentValues)
matcher.addURI(authority, PhotoContract.PATH_PHOTO + "/#/" + PhotoContract.PATH_COMMENT, PHOTO_COMMENT);
// matches photo/<photo id>/author/ (author name in ContentValues)
//matcher.addURI(authority, PhotoContract.PATH_PHOTO + "/#/" + PhotoContract.PATH_AUTHOR, PHOTO_AUTHOR);
return matcher;
}
@Override
public String getType(Uri uri) {
// Use the Uri Matcher to determine what kind of URI this is.
final int match = sUriMatcher.match(uri);
// Note: We always return single row of data, so content-type is always "a dir"
switch (match) {
case PHOTO_COMMENT:
return PhotoContract.PhotoEntry.CONTENT_TYPE;
case PHOTO_AUTHOR:
return PhotoContract.PhotoEntry.CONTENT_TYPE;
case PHOTO:
return PhotoContract.PhotoEntry.CONTENT_TYPE;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
}
@Override
public boolean onCreate() {
return true;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
MatrixCursor retCursor = new MatrixCursor(projection);
// open the specified image through the MediaStore to get base columns
// then open image file through ExifInterface to get detail columns
Long IMAGE_ID = PhotoContract.PhotoEntry.getImageIdFromUri(uri);
Uri baseUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
baseUri = Uri.withAppendedPath(baseUri, ""+ IMAGE_ID);
// http://androidsnippets.com/get-file-path-of-gallery-image
// run query against MediaStore, projection = null means "get all fields"
Cursor c = getContext().getContentResolver().query(baseUri, null, null, null, null);
if (!c.moveToFirst()) {
return null;
}
// match returned fields against projection, and copy into row[]
Object[] row = new Object[projection.length];
int i = 0;
/* // Cursor.getType() Requires API level > 10...
for (String colName : projection) {
int idx = c.getColumnIndex(colName);
if (idx <= 0) return null; // ERROR
int colType = c.getType(idx);
switch (colType) {
case Cursor.FIELD_TYPE_INTEGER: {
row[i++] = c.getLong(idx);
break;
}
case Cursor.FIELD_TYPE_FLOAT: {
row[i++] = c.getFloat(idx);
break;
}
case Cursor.FIELD_TYPE_STRING: {
row[i++] = c.getString(idx);
break;
}
case Cursor.FIELD_TYPE_BLOB: {
row[i++] = c.getBlob(idx);
break;
}
}
}
*/
//http://stackoverflow.com/questions/11658239/cursor-gettype-for-api-level-11
CursorWrapper cw = (CursorWrapper)c;
Class<?> cursorWrapper = CursorWrapper.class;
Field mCursor = null;
try {
mCursor = cursorWrapper.getDeclaredField("mCursor");
mCursor.setAccessible(true);
AbstractWindowedCursor abstractWindowedCursor = (AbstractWindowedCursor)mCursor.get(cw);
CursorWindow cursorWindow = abstractWindowedCursor.getWindow();
int pos = abstractWindowedCursor.getPosition();
// NB! Expect resulting cursor to contain data in same order as projection!
for (String colName : projection) {
int idx = c.getColumnIndex(colName);
// simple solution: If column name NOT FOUND in MediaStore, assume it's an EXIF tag
// and skip
if (idx >= 0) {
if (cursorWindow.isNull(pos, idx)) {
//Cursor.FIELD_TYPE_NULL
row[i++] = null;
} else if (cursorWindow.isLong(pos, idx)) {
//Cursor.FIELD_TYPE_INTEGER
row[i++] = c.getLong(idx);
} else if (cursorWindow.isFloat(pos, idx)) {
//Cursor.FIELD_TYPE_FLOAT
row[i++] = c.getFloat(idx);
} else if (cursorWindow.isString(pos, idx)) {
//Cursor.FIELD_TYPE_STRING
row[i++] = c.getString(idx);
} else if (cursorWindow.isBlob(pos, idx)) {
//Cursor.FIELD_TYPE_BLOB
row[i++] = c.getBlob(idx);
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
// have now handled the first i fields in projection. If there are any more, we expect
// these to be valid EXIF tags. Should obviously make this more robust...
try {
ExifInterface exif = new ExifInterface((String) row[2]);
while (i < projection.length) {
row[i] = exif.getAttribute("UserComment"); //projection[i]); // String (or null)
i++;
}
} catch (IOException e) {
e.printStackTrace();
}
retCursor.addRow(row);
return retCursor;
}
@Override
public Uri insert(Uri uri, ContentValues values) {
return null;
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
return 0;
}
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
// URI identifies IMAGE_ID and which EXIF tag to set; content://AUTH/photo/<image_id>/comment or /author
// first, get IMAGE_ID and prepare URI (to get file path from MediaStore)
Long IMAGE_ID = PhotoContract.PhotoEntry.getImageIdFromUri(uri);
Uri baseUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
baseUri = Uri.withAppendedPath(baseUri, ""+ IMAGE_ID);
// get DATA (path/filename) from MediaStore -- only need that specific piece of information
String[] MS_projection = {MediaStore.Images.Media.DATA};
// http://androidsnippets.com/get-file-path-of-gallery-image
Cursor c = getContext().getContentResolver().query(baseUri, MS_projection, null, null, null);
if (!c.moveToFirst()) return -1; // can't get image path/filename...
String thumbData = c.getString(0);
// then, use URIMatcher to identify the "operation" (i.e., which tag to set)
final int match = sUriMatcher.match(uri);
String EXIF_tag;
switch (match) {
case PHOTO_COMMENT: {
EXIF_tag = "UserComment";
break;
}
case PHOTO_AUTHOR: {
EXIF_tag = "Author";
break;
}
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
if (EXIF_tag == null) return -1;
// finally, set tag in image
try {
ExifInterface exif = new ExifInterface(thumbData);
String textToSet = values.get(EXIF_tag).toString();
if (textToSet == null)
throw new IOException("Can't retrieve text to set from ContentValues, on key = " + EXIF_tag);
if (textToSet.length() > 48)
throw new IOException("Data too long (" + textToSet.length() + "), on key = " + EXIF_tag);
exif.setAttribute(EXIF_tag, textToSet);
exif.saveAttributes();
} catch (IOException e) {
e.printStackTrace();
}
return 1; // 1 image updated
}
}
可以接受char数组并创建一个可序列化的Clob对象。
你可以参考这里 http://docs.oracle.com/javase/7/docs/api/javax/sql/rowset/serial/SerialClob.html
javax.sql.rowset.serial.SerialClob可以接受字节数组
你可以参考这里 http://docs.oracle.com/javase/7/docs/api/javax/sql/rowset/serial/SerialBlob.html