datapage.java

非常棒的java数据库

            break;
        case Value.LONG:
            writeLong(v.getLong());
            break;
        case Value.DECIMAL:
            String s = v.getString();
            writeString(s);
            break;
        case Value.TIME:
            writeLong(v.getTimeNoCopy().getTime());
            break;
        case Value.DATE:
            writeLong(v.getDateNoCopy().getTime());
            break;
        case Value.TIMESTAMP: {
            Timestamp ts = v.getTimestampNoCopy();
            writeLong(ts.getTime());
            writeInt(ts.getNanos());
            break;
        }
        case Value.JAVA_OBJECT:
        case Value.BYTES: {
            byte[] b = v.getBytesNoCopy();
            writeInt(b.length);
            write(b, 0, b.length);
            break;
        }
        case Value.UUID: {
            ValueUuid uuid = (ValueUuid) v;
            writeLong(uuid.getHigh());
            writeLong(uuid.getLow());
            break;
        }
        case Value.STRING:
        case Value.STRING_IGNORECASE:
        case Value.STRING_FIXED:
            writeString(v.getString());
            break;
        case Value.DOUBLE:
            writeLong(Double.doubleToLongBits(v.getDouble()));
            break;
        case Value.FLOAT:
            writeInt(Float.floatToIntBits(v.getFloat()));
            break;
        case Value.BLOB:
        case Value.CLOB: {
            ValueLob lob = (ValueLob) v;
            lob.convertToFileIfRequired(handler);
            byte[] small = lob.getSmall();
            if (small == null) {
                // -2 for historical reasons (-1 didn't store precision)
                int type = -2;
                if (!lob.isLinked()) {
                    type = -3;
                }
                writeInt(type);
                writeInt(lob.getTableId());
                writeInt(lob.getObjectId());
                writeLong(lob.getPrecision());
                writeByte((byte) (lob.useCompression() ? 1 : 0));
                if (type == -3) {
                    writeString(lob.getFileName());
                }
            } else {
                writeInt(small.length);
                write(small, 0, small.length);
            }
            break;
        }
        case Value.ARRAY: {
            Value[] list = ((ValueArray) v).getList();
            writeInt(list.length);
            for (int i = 0; i < list.length; i++) {
                writeValue(list[i]);
            }
            break;
        }
        default:
            throw Message.getInternalError("type=" + v.getType());
        }
        if (SysProperties.CHECK2) {
            if (pos - start != getValueLen(v)) {
                throw Message
                        .getInternalError("value size error: got " + (pos - start) + " expected " + getValueLen(v));
            }
        }
    }

    public int getValueLen(Value v) throws SQLException {
        if (v == ValueNull.INSTANCE) {
            return 1;
        }
        switch (v.getType()) {
        case Value.BOOLEAN:
        case Value.BYTE:
        case Value.SHORT:
        case Value.INT:
            return 1 + getIntLen();
        case Value.LONG:
            return 1 + getLongLen(v.getLong());
        case Value.DOUBLE:
            return 1 + getLongLen(Double.doubleToLongBits(v.getDouble()));
        case Value.FLOAT:
            return 1 + getIntLen();
        case Value.STRING:
        case Value.STRING_IGNORECASE:
        case Value.STRING_FIXED:
            return 1 + getStringLen(v.getString());
        case Value.DECIMAL:
            return 1 + getStringLen(v.getString());
        case Value.JAVA_OBJECT:
        case Value.BYTES: {
            int len = v.getBytesNoCopy().length;
            return 1 + getIntLen() + len;
        }
        case Value.UUID: {
            ValueUuid uuid = (ValueUuid) v;
            return 1 + getLongLen(uuid.getHigh()) + getLongLen(uuid.getLow());
        }
        case Value.TIME:
            return 1 + getLongLen(v.getTimeNoCopy().getTime());
        case Value.DATE:
            return 1 + getLongLen(v.getDateNoCopy().getTime());
        case Value.TIMESTAMP: {
            Timestamp ts = v.getTimestampNoCopy();
            return 1 + getLongLen(ts.getTime()) + getIntLen();
        }
        case Value.BLOB:
        case Value.CLOB: {
            int len = 1;
            ValueLob lob = (ValueLob) v;
            lob.convertToFileIfRequired(handler);
            byte[] small = lob.getSmall();
            if (small != null) {
                len += getIntLen() + small.length;
            } else {
                len += getIntLen() + getIntLen() + getIntLen() + getLongLen(lob.getPrecision()) + 1;
                if (!lob.isLinked()) {
                    len += getStringLen(lob.getFileName());
                }
            }
            return len;
        }
        case Value.ARRAY: {
            Value[] list = ((ValueArray) v).getList();
            int len = 1 + getIntLen();
            for (int i = 0; i < list.length; i++) {
                len += getValueLen(list[i]);
            }
            return len;
        }
        default:
            throw Message.getInternalError("type=" + v.getType());
        }
    }

    public Value readValue() throws SQLException {
        int dataType = data[pos++];
        if (dataType == '-') {
            return ValueNull.INSTANCE;
        }
        dataType = (dataType - 'a');
        switch (dataType) {
        case Value.BOOLEAN:
            return ValueBoolean.get(readInt() == 1);
        case Value.BYTE:
            return ValueByte.get((byte) readInt());
        case Value.SHORT:
            return ValueShort.get((short) readInt());
        case Value.INT:
            return ValueInt.get(readInt());
        case Value.LONG:
            return ValueLong.get(readLong());
        case Value.DECIMAL:
            return ValueDecimal.get(new BigDecimal(readString()));
        case Value.DATE:
            return ValueDate.getNoCopy(new Date(readLong()));
        case Value.TIME:
            // need to normalize the year, month and day
            return ValueTime.get(new Time(readLong()));
        case Value.TIMESTAMP: {
            Timestamp ts = new Timestamp(readLong());
            ts.setNanos(readInt());
            return ValueTimestamp.getNoCopy(ts);
        }
        case Value.JAVA_OBJECT: {
            int len = readInt();
            byte[] b = new byte[len];
            read(b, 0, len);
            return ValueJavaObject.getNoCopy(b);
        }
        case Value.BYTES: {
            int len = readInt();
            byte[] b = new byte[len];
            read(b, 0, len);
            return ValueBytes.getNoCopy(b);
        }
        case Value.UUID:
            return ValueUuid.get(readLong(), readLong());
        case Value.STRING:
            return ValueString.get(readString());
        case Value.STRING_IGNORECASE:
            return ValueStringIgnoreCase.get(readString());
        case Value.STRING_FIXED:
            return ValueStringFixed.get(readString());
        case Value.DOUBLE:
            return ValueDouble.get(Double.longBitsToDouble(readLong()));
        case Value.FLOAT:
            return ValueFloat.get(Float.intBitsToFloat(readInt()));
        case Value.BLOB:
        case Value.CLOB: {
            int smallLen = readInt();
            if (smallLen >= 0) {
                byte[] small = new byte[smallLen];
                read(small, 0, smallLen);
                return ValueLob.createSmallLob(dataType, small);
            } else {
                int tableId = readInt();
                int objectId = readInt();
                long precision = 0;
                boolean compression = false;
                // -2 is for historical reasons (-1 didn't store precision)
                if (smallLen == -2 || smallLen == -3) {
                    precision = readLong();
                    compression = readByte() == 1;
                }
                ValueLob lob = ValueLob.open(dataType, handler, tableId, objectId, precision, compression);
                if (smallLen == -3) {
                    lob.setFileName(readString());
                }
                return lob;
            }
        }
        case Value.ARRAY: {
            int len = readInt();
            Value[] list = new Value[len];
            for (int i = 0; i < len; i++) {
                list[i] = readValue();
            }
            return ValueArray.get(list);
        }
        default:
            throw Message.getInternalError("type=" + dataType);
        }
    }

    public void fillAligned() {
        // TODO datapage: fillAligned should not use a fixed constant '2'
        // 0..6 > 8, 7..14 > 16, 15..22 > 24, ...
        fill(MathUtils.roundUp(pos + 2, Constants.FILE_BLOCK_SIZE));
    }

    public void setPos(int pos) {
        this.pos = pos;
    }

}