我在從數據庫中正確檢索自己的類「BallotPaper」的特定對象時遇到問題。它可以正確保存,但在創建ObjectInputStream時會引發異常。嘗試從數據庫中檢索對象時出現Java,JDBC:StreamCorruptedException
當然,我已經閱讀了許多類似的問題和答案,但仍然無法處理它。
在數據庫中我有一個bytea類型的列(它是postgreSQL),我保存我的對象。
下面是幾行代碼:
//Saving the object 'paper' of the class 'BallotPaper'
PreparedStatement st = connection.prepareStatement(query);
ByteArrayOutputStream byos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(byos);
oos.writeObject(paper);
byte[] bytePaper = byos.toByteArray();
st.setBytes(1, bytePaper);
st.executeUpdate();
byos.close();
oos.close();
st.close();
//Trying to retrieve the object:
String query2 = "SELECT paper FROM voters WHERE id="+_id+";";
Statement s = connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
ResultSet r = s.executeQuery(query2);
r.first();
bytePaper = r.getBytes(1);
ByteArrayInputStream b = new ByteArrayInputStream(bytePaper);
ObjectInputStream o = new ObjectInputStream(b); // *
BallotPaper ba = (BallotPaper)o.readObject();
拋出異常,最後前行,標有*。
它看起來像:
java.io.StreamCorruptedException: invalid stream header: BB656430
at java.io.ObjectInputStream.readStreamHeader(Unknown Source)
at java.io.ObjectInputStream.<init>(Unknown Source)
at slave.VotersDB.saveFilledPaper(VotersDB.java:162)
at slave.ClientThread.prepareResponse(ClientThread.java:50)
at slave.ClientThread.run(ClientThread.java:72)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
感謝所有的答案。
不幸的是,它不適用於flush()。 保存後,我關閉了所有的流。 – brzeszczot