我正在尝试使用 JDBC 在 Oracle 数据库上创建 Java 源对象。
我要创建的源如下：
create or replace and resolve java source named "BlobIO" as package dbjava;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.io.*;
public class BlobIO {
/**
* Stores a blob into a local file (or even UNC-path)
* @param blob The blob locator that should be stored in a file
* @param filename The filename to write to
* @param bufferSize The buffer size for data transfer
* @return 1 if successful, 0 if failed
*/
public static int blobToFile(java.sql.Blob blob, String filename, int bufferSize)
{
OutputStream os = null;
InputStream is = null;
boolean fail = true;
try {
is = blob.getBinaryStream();
os = new FileOutputStream(filename);
int amountRead = 0;
byte[] buffer = new byte[bufferSize];
while ((amountRead = is.read(buffer, 0, buffer.length)) != -1) {
os.write(buffer, 0, amountRead);
}
is.close();
os.flush();
os.close();
fail = false;
} catch (IOException ex) {
new File(filename).delete();
System.err.println("Could not store blob to file.");
System.err.println("File : " + filename);
System.err.println("Reason : " + ex.getClass().getName() + " : " + ex.getMessage());
fail = true;
} catch (SQLException ex) {
new File(filename).delete();
System.err.println("Could not store blob to file.");
System.err.println("File : " + filename);
System.err.println("Reason : " + ex.getClass().getName() + " : " + ex.getMessage());
fail = true;
} finally {
try {is.close();} catch (Exception ex) {}
try {os.flush();} catch (Exception ex) {}
try {os.close();} catch (Exception ex) {}
}
return fail? 0:1;
}
/**
* Stores a blob into a local file (or even UNC-path)
* @param query The query that should select ONLY the blob field
* @param filename The filename to write to
* @param bufferSize The buffer size for data transfer
* @return 1 if successful, 0 if failed
*/
public static int blobToFile(String query, String filename, int bufferSize) {
try {
Connection conn = DriverManager.getConnection("jdbc:default:connection:");
Statement stmt = conn.createStatement();
ResultSet rset = stmt.executeQuery(query);
InputStream is;
if (rset.next())
{
int ret = blobToFile(rset.getBlob(1), filename, bufferSize);
if (rset.next())
{
new File(filename).delete();
System.err.println("Could not store blob to file.");
System.err.println("Blob query : " + query);
System.err.println("File : " + filename);
System.err.println("Reason : too many rows");
rset.close();
stmt.close();
return 0;
} else {
rset.close();
stmt.close();
return ret;
}
} else {
System.err.println("Could not store blob to file.");
System.err.println("Blob query : " + query);
System.err.println("File : " + filename);
System.err.println("Reason : no records retrieved by query");
rset.close();
stmt.close();
return 0;
}
} catch (Exception e) {
System.err.println(e.getMessage());
return 0;
}
}
}
/
我尝试过CallableStatement使用 execute 方法，这给了我error: "Missing IN/OUT parameters"
当我尝试在普通Statement对象上使用 execute 方法时出现错误："
Non supported SQL92 token at position: 262"
任何人都知道我做错了什么？似乎也无法在谷歌上找到任何东西。
编辑：这是我用来尝试执行脚本的代码（字符串sql包含您可以在上面看到的脚本，变量conn是Connection对象。
CallableStatement stat = conn.prepareCall(sql);
stat.setEscapeProcessing(false);
stat.execute();
如果我尝试仅使用 Statement 它是这样的：
Statement stat = conn.createStatement();
stat.execute(sql);