oracle 插入大文本，字节转浮点数

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key: oracle插入超长文本;oracle 插入大数据
参考这篇写得很好不再累述
补充
建表语句

create table  TESTCLOB(  id      NUMBER(6),  name    VARCHAR2(20) not null,  CLOBATTR   CLOB  not null)

package com.grid.test;import java.io.File;import java.io.IOException;import java.io.RandomAccessFile;import java.nio.MappedByteBuffer;import java.nio.channels.FileChannel;import java.nio.channels.FileChannel.MapMode;import java.sql.SQLException;public class ReadFIleData {    public static void main(String[] args) {        // 读取目录下.data文件   类型 时间 rader_201304.data _ 分隔符        String filePath = "F:/Maobo_Files/微气候细网格城市资源/最终数据/外网data/";        File filepath = new File(filePath);        String[] fname = filepath.list();        for (String s : fname) {            if (s.endsWith(".data")) {                String type = s.split("_")[0];                String datetime = s.split("_")[1];                String dtime = datetime.substring(0, datetime.lastIndexOf("."));                String fpath = filePath + s;                try {                    writeData(type, dtime, fpath);                } catch (SQLException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                } catch (IOException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }            }        }    }    private static void writeData(String type, String datetime, String fpath) throws SQLException, IOException {        byte[] bys = null;        StringBuffer sb = new StringBuffer();        bys = toByteArray3(fpath);        float[] qpe = new float[bys.length / 4];        System.out.println("共计：" + qpe.length);        for (int i = 0; i < qpe.length; i++) {            float ft = byte2float(bys, i * 4);            sb.append(ft < 0 ? 0 : ft);            sb.append(",");        }        System.out.println("sb:" + sb.toString());        // 入库        TestClobIn.doinsert(sb.toString(), type, datetime);    }    /**     * 字节转换为浮点     *      * @param b     *            字节（至少4个字节）     * @param index     *            开始位置     * @return     */    public static float byte2float(byte[] b, int index) {        int fl;        fl = b[index + 0];        fl &= 0xff;        fl |= ((long) b[index + 1] << 8);        fl &= 0xffff;        fl |= ((long) b[index + 2] << 16);        fl &= 0xffffff;        fl |= ((long) b[index + 3] << 24);        return Float.intBitsToFloat(fl);    }    /**     * Mapped File way MappedByteBuffer 可以在处理大文件时，提升性能     *      * @param filename     * @return     * @throws IOException     */    public static byte[] toByteArray3(String filename) throws IOException {        FileChannel fc = null;        try {            fc = new RandomAccessFile(filename, "r").getChannel();            MappedByteBuffer byteBuffer = fc.map(MapMode.READ_ONLY, 0, fc.size()).load();            System.out.println(" is load: " + byteBuffer.isLoaded());            byte[] result = new byte[(int) fc.size()];            if (byteBuffer.remaining() > 0) {                // System.out.println("remain");                byteBuffer.get(result, 0, byteBuffer.remaining());            }            return result;        } catch (IOException e) {            e.printStackTrace();            throw e;        } finally {            try {                fc.close();            } catch (IOException e) {                e.printStackTrace();            }        }    }}//部分源码来自网络，恕不能找到出处了

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