[英]Create PDF using byte array from database
我正在嘗試從來自數據庫的字節數組中創建pdf文件。代碼運行良好並創建了pdf文件,但是我無法打開該文件,它表明文件已損壞或損壞。 在這里,我顯示了完整的代碼,請指出要更改的代碼或實現此類型代碼的正確方法。 謝謝。
TestPDF:
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
public class TestPDF {
public static void main(String[] args) throws FileNotFoundException {
String jdbcClassName="com.ibm.db2.jcc.DB2Driver";
String host="hostname",port="50000",db="dbname",dbuser="user",dbpass="pass";
String url="jdbc:db2://"+host+":"+port+"/"+db;
String user=dbuser;
String password=dbpass;
Connection con = null;
InputStream fetchStream = null;
try{
//Load class into memory
Class.forName(jdbcClassName);
//Establish connection
con = DriverManager.getConnection(url, user, password);
PreparedStatement pstmt = con.prepareStatement("select * from tgpoa01.aud_trail_dtl WHERE AUD_TRAIL_REC_ID = '-9223372036798517556'");
ResultSet rs = pstmt.executeQuery();
if(rs.next())
{
fetchStream = rs.getBinaryStream("AUD_TRAIL_MSG_TX");
if(rs.getString("AUD_PRCS_STAGE_CD").equals("CONT")){
ByteArrayOutputStream bos = new ByteArrayOutputStream();
byte[] buf = new byte[1024];
try {
for (int readNum; (readNum = fetchStream.read(buf)) != -1;) {
bos.write(buf, 0, readNum);
System.out.println("read " + readNum + " bytes,");
}
System.out.println("Byte array is="+bos);
} catch (Exception ex) {
ex.printStackTrace();
}
byte[] bytes = bos.toByteArray();
File someFile = new File("d://Output_File.pdf");
try{
FileOutputStream fos = new FileOutputStream(someFile);
fos.write(bytes);
fos.flush();
fos.close();
}catch(Exception e){
}
}
}
}catch(Exception e){
System.out.println("Exception in getting PDF : "+e);
}
}
}
您用來從數據庫讀取bytes
的for
循環對我來說有點奇怪。 您可以嘗試以下( 完全未經測試的 )替代方法之一:
使用ResultSet.getBinaryStream(...)
:
if ( rs.next() ) {
if ( rs.getString("AUD_PRCS_STAGE_CD").equals("CONT") ) {
File someFile = new File("d://Output_File.pdf");
FileOutputStream fos = new FileOutputStream(someFile);
byte[] buffer = new byte[1];
fetchStream = rs.getBinaryStream("AUD_TRAIL_MSG_TX");
while (fetchStream.read(buffer) > 0) {
fos.write(buffer);
}
fos.close();
}
}
使用ResultSet.getBlob(...)
:
if ( rs.next() ) {
if ( rs.getString("AUD_PRCS_STAGE_CD").equals("CONT") ) {
Blob blob = rs.getBlob("AUD_TRAIL_MSG_TX");
byte[] bytes = blob.getBytes(1, (int)blob.length());
File someFile = new File("d://Output_File.pdf");
FileOutputStream fos = new FileOutputStream(someFile);
fos.write(bytes);
fos.flush();
fos.close();
}
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.