java实现文件上传到服务器

package com.funi.help; import java.io.BufferedInputStream; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.sql.Blob; import java.sql.SQLException; public class BlobImpl implements Blob { private byte[] _bytes = new byte[0]; private int _length = 0; /** * 构造函数，以byte[]构建blob * * @param bytes */ public BlobImpl(byte[] bytes) { init(bytes); } /** * 构造函数，以InputStream构建blob * * @param bytes */ public BlobImpl(InputStream input) { init(FileHelper.read(input)); } /** * 构造函数，以blob重新构建blob * * @param bytes */ public BlobImpl(Blob blob) { init(blobToBytes(blob)); } /** * 初始化byte[] * * @param b */ private void init(byte[] bytes) { _bytes = bytes; _length = _bytes.length; } /** * 将blob转为byte[] * * @param blob * @return */ private byte[] blobToBytes(Blob blob) { BufferedInputStream is = null; try { is = new BufferedInputStream(blob.getBinaryStream()); byte[] bytes = new byte[(int) blob.length()]; int len = bytes.length; int offset = 0; int read = 0; while (offset < len && (read = is.read(bytes, offset, len - offset)) >= 0) { offset += read; } return bytes; } catch (Exception e) { return null; } finally { try { is.close(); is = null; } catch (IOException e) { return null; } } } /** * 获得blob中数据实际长度 * * @return * @throws SQLException */ public long length() throws SQLException { return _bytes.length; } /** * 返回指定长度的byte[] * * @param pos * @param len * @return * @throws SQLException */ public byte[] getBytes(long pos, int len) throws SQLException { if (pos == 0 && len == length()) return _bytes; try { byte[] newbytes = new byte[len]; System.arraycopy(_bytes, (int) pos, newbytes, 0, len); return newbytes; } catch (Exception e) { throw new SQLException("Inoperable scope of this array"); } } /** * 返回InputStream * * @return * @throws SQLException */ public InputStream getBinaryStream() throws SQLException { return new ByteArrayInputStream(_bytes); } /** * 获取此byte[]中start的字节位置 * * @param pattern * @param start * @return * @throws SQLException */ public long position(byte[] pattern, long start) throws SQLException { start--; if (start < 0) { throw new SQLException("start < 0"); } if (start >= _length) { throw new SQLException("start >= max length"); } if (pattern == null) { throw new SQLException("pattern == null"); } if (pattern.length == 0 || _length == 0 || pattern.length > _length) { return -1; } int limit = (int) _length - pattern.length; for (int i = (int) start; i <= limit; i++) { int p; for (p = 0; p < pattern.length && _bytes[i + p] == pattern[p]; p++) { if (p == pattern.length) { return i + 1; } } } return -1; } /** * 获取指定的blob中start的字节位置 * * @param pattern * @param start * @return * @throws SQLException */ public long position(Blob pattern, long start) throws SQLException { return position(blobToBytes(pattern), start); } /** * 不支持操作异常抛出 * */ void nonsupport() { throw new UnsupportedOperationException("This method is not supported！"); } /** * 释放Blob对象资源 * * @throws SQLException */ public void free() throws SQLException { _bytes = new byte[0]; _length = 0; } /** * 返回指定长度部分的InputStream，并返回InputStream * * @param pos * @param len * @return * @throws SQLException */ public InputStream getBinaryStream(long pos, long len) throws SQLException { return new ByteArrayInputStream(getBytes(pos, (int) len)); } /** * 以指定指定长度将二进制流写入OutputStream，并返回OutputStream * * @param pos * @return * @throws SQLException */ public OutputStream setBinaryStream(long pos) throws SQLException { // 暂不支持 nonsupport(); pos--; if (pos < 0) { throw new SQLException("pos < 0"); } if (pos > _length) { throw new SQLException("pos > length"); } // 将byte[]转为ByteArrayInputStream ByteArrayInputStream inputStream = new ByteArrayInputStream(_bytes); ByteArrayOutputStream os = new ByteArrayOutputStream(); byte[] bytes = new byte[(int) pos]; try { bytes = new byte[inputStream.available()]; int read; while ((read = inputStream.read(bytes)) >= 0) { os.write(bytes, 0, read); } } catch (IOException e) { e.getStackTrace(); } // 返回OutputStream return (OutputStream) os; } /** * 设定byte[] * * @param pos * @param bytes * @param offset * @param size * @param copy * @return * @throws SQLException */ private int setBytes(long pos, byte[] bytes, int offset, int size, boolean copy) throws SQLException { // 暂不支持 nonsupport(); pos--; if (pos < 0) { throw new SQLException("pos < 0"); } if (pos > _length) { throw new SQLException("pos > max length"); } if (bytes == null) { throw new SQLException("bytes == null"); } if (offset < 0 || offset > bytes.length) { throw new SQLException("offset < 0 || offset > bytes.length"); } if (size < 0 || pos + size > (long) Integer.MAX_VALUE || offset + size > bytes.length) { throw new SQLException(); } // 当copy数据时 if (copy) { _bytes = new byte[size]; System.arraycopy(bytes, offset, _bytes, 0, size); } else { // 否则直接替换对象 _bytes = bytes; } return _bytes.length; } /** * 设定指定开始位置byte[] * * @param pos * @param bytes * @return * @throws SQLException */ public int setBytes(long pos, byte[] bytes) throws SQLException { // 暂不支持 nonsupport(); return setBytes(pos, bytes, 0, bytes.length, true); } /** * 设定byte[] * * @param pos * @param bytes * @param offset * @param len * @return * @throws SQLException */ public int setBytes(long pos, byte[] bytes, int offset, int len) throws SQLException { // 暂不支持 nonsupport(); return setBytes(pos, bytes, offset, len, true); } /** * 截取相应部分数据 * * @param len * @throws SQLException */ public void truncate(long len) throws SQLException { if (len < 0) { throw new SQLException("len < 0"); } if (len > _length) { throw new SQLException("len > max length"); } _length = (int) len; } public static void main(String[] args) { // 获得一个指定文件的blob // PS:天地良心啊，没抄袭hibernate写法，无奈的写一样了，不过比他多实现了点方法……（还特意把函数改名，不然更像|||）…… Blob blob = Loon.makeBlob("D:\test.txt"); // 以byte[]获得blob实例 // Blob blob = new BlobImpl(bytes); try { // getBytes测试 // 取出0到blob结束范围的byte[] byte[] buffer = blob.getBytes(0, (int) blob.length()); // 以gb2312编码将byte[]转为string显示 System.out.println(new String(buffer, "gb2312")); // getBinaryStream测试 BufferedInputStream is = new BufferedInputStream( blob.getBinaryStream()); buffer = new byte[(int) blob.length()]; int len = buffer.length; int offset = 0; int read = 0; while (offset < len && (read = is.read(buffer, offset, len - offset)) >= 0) { offset += read; } System.out.println(new String(buffer, "gb2312")); // getBinarySt