/*
* Copyright 2004-2014 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.value;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;
import java.lang.ref.SoftReference;
import java.math.BigDecimal;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Time;
import java.sql.Timestamp;
import java.sql.Types;
import org.h2.api.ErrorCode;
import org.h2.engine.Constants;
import org.h2.engine.SysProperties;
import org.h2.message.DbException;
import org.h2.store.DataHandler;
import org.h2.tools.SimpleResultSet;
import org.h2.util.DateTimeUtils;
import org.h2.util.JdbcUtils;
import org.h2.util.MathUtils;
import org.h2.util.StringUtils;
import org.h2.util.Utils;
/**
* This is the base class for all value classes.
* It provides conversion and comparison methods.
*
* @author Thomas Mueller
* @author Noel Grandin
* @author Nicolas Fortin, Atelier SIG, IRSTV FR CNRS 24888
*/
public abstract class Value {
/**
* The data type is unknown at this time.
*/
public static final int UNKNOWN = -1;
/**
* The value type for NULL.
*/
public static final int NULL = 0;
/**
* The value type for BOOLEAN values.
*/
public static final int BOOLEAN = 1;
/**
* The value type for BYTE values.
*/
public static final int BYTE = 2;
/**
* The value type for SHORT values.
*/
public static final int SHORT = 3;
/**
* The value type for INT values.
*/
public static final int INT = 4;
/**
* The value type for LONG values.
*/
public static final int LONG = 5;
/**
* The value type for DECIMAL values.
*/
public static final int DECIMAL = 6;
/**
* The value type for DOUBLE values.
*/
public static final int DOUBLE = 7;
/**
* The value type for FLOAT values.
*/
public static final int FLOAT = 8;
/**
* The value type for TIME values.
*/
public static final int TIME = 9;
/**
* The value type for DATE values.
*/
public static final int DATE = 10;
/**
* The value type for TIMESTAMP values.
*/
public static final int TIMESTAMP = 11;
/**
* The value type for BYTES values.
*/
public static final int BYTES = 12;
/**
* The value type for STRING values.
*/
public static final int STRING = 13;
/**
* The value type for case insensitive STRING values.
*/
public static final int STRING_IGNORECASE = 14;
/**
* The value type for BLOB values.
*/
public static final int BLOB = 15;
/**
* The value type for CLOB values.
*/
public static final int CLOB = 16;
/**
* The value type for ARRAY values.
*/
public static final int ARRAY = 17;
/**
* The value type for RESULT_SET values.
*/
public static final int RESULT_SET = 18;
/**
* The value type for JAVA_OBJECT values.
*/
public static final int JAVA_OBJECT = 19;
/**
* The value type for UUID values.
*/
public static final int UUID = 20;
/**
* The value type for string values with a fixed size.
*/
public static final int STRING_FIXED = 21;
/**
* The value type for string values with a fixed size.
*/
public static final int GEOMETRY = 22;
/**
* 23 was a short-lived experiment "TIMESTAMP UTC" which has been removed.
*/
/**
* The value type for TIMESTAMP WITH TIME ZONE values.
*/
public static final int TIMESTAMP_TZ = 24;
/**
* The number of value types.
*/
public static final int TYPE_COUNT = TIMESTAMP_TZ;
private static SoftReference<Value[]> softCache =
new SoftReference<Value[]>(null);
private static final BigDecimal MAX_LONG_DECIMAL =
BigDecimal.valueOf(Long.MAX_VALUE);
private static final BigDecimal MIN_LONG_DECIMAL =
BigDecimal.valueOf(Long.MIN_VALUE);
/**
* Get the SQL expression for this value.
*
* @return the SQL expression
*/
public abstract String getSQL();
/**
* Get the value type.
*
* @return the type
*/
public abstract int getType();
/**
* Get the precision.
*
* @return the precision
*/
public abstract long getPrecision();
/**
* Get the display size in characters.
*
* @return the display size
*/
public abstract int getDisplaySize();
/**
* Get the memory used by this object.
*
* @return the memory used in bytes
*/
public int getMemory() {
return DataType.getDataType(getType()).memory;
}
/**
* Get the value as a string.
*
* @return the string
*/
public abstract String getString();
/**
* Get the value as an object.
*
* @return the object
*/
public abstract Object getObject();
/**
* Set the value as a parameter in a prepared statement.
*
* @param prep the prepared statement
* @param parameterIndex the parameter index
*/
public abstract void set(PreparedStatement prep, int parameterIndex)
throws SQLException;
/**
* Compare the value with another value of the same type.
*
* @param v the other value
* @param mode the compare mode
* @return 0 if both values are equal, -1 if the other value is smaller, and
* 1 otherwise
*/
protected abstract int compareSecure(Value v, CompareMode mode);
@Override
public abstract int hashCode();
/**
* Check if the two values have the same hash code. No data conversion is
* made; this method returns false if the other object is not of the same
* class. For some values, compareTo may return 0 even if equals return
* false. Example: ValueDecimal 0.0 and 0.00.
*
* @param other the other value
* @return true if they are equal
*/
@Override
public abstract boolean equals(Object other);
/**
* Get the order of this value type.
*
* @param type the value type
* @return the order number
*/
static int getOrder(int type) {
//当两个值需要发生转换时，order数字小的要转到数字大的，比如a是int，b是long，int是23，long是24，那么在做运算时a要转成long
switch (type) {
case UNKNOWN:
return 1;
case NULL:
return 2;
case STRING:
return 10;
case CLOB:
return 11;
case STRING_FIXED:
return 12;
case STRING_IGNORECASE:
return 13;
case BOOLEAN:
return 20;
case BYTE:
return 21;
case SHORT:
return 22;
case INT:
return 23;
case LONG:
return 24;
case DECIMAL:
return 25;
case FLOAT:
return 26;
case DOUBLE:
return 27;
case TIME:
return 30;
case DATE:
return 31;
case TIMESTAMP:
return 32;
case TIMESTAMP_TZ:
return 34;
case BYTES:
return 40;
case BLOB:
return 41;
case JAVA_OBJECT:
return 42;
case UUID:
return 43;
case GEOMETRY:
return 44;
case ARRAY:
return 50;
case RESULT_SET:
return 51;
default:
throw DbException.throwInternalError("type:"+type);
}
}
/**
* Get the higher value order type of two value types. If values need to be
* converted to match the other operands value type, the value with the
* lower order is converted to the value with the higher order.
*
* @param t1 the first value type
* @param t2 the second value type
* @return the higher value type of the two
*/
public static int getHigherOrder(int t1, int t2) {
if (t1 == Value.UNKNOWN || t2 == Value.UNKNOWN) {
if (t1 == t2) {
throw DbException.get(
ErrorCode.UNKNOWN_DATA_TYPE_1, "?, ?");
} else if (t1 == Value.NULL) {
throw DbException.get(
ErrorCode.UNKNOWN_DATA_TYPE_1, "NULL, ?");
} else if (t2 == Value.NULL) {
throw DbException.get(
ErrorCode.UNKNOWN_DATA_TYPE_1, "?, NULL");
}
}
if (t1 == t2) {
return t1;
}
int o1 = getOrder(t1);
int o2 = getOrder(t2);
return o1 > o2 ? t1 : t2;
}
/**
* Check if a value is in the cache that is equal to this value. If yes,
* this value should be used to save memory. If the value is not in the
* cache yet, it is added.
*
* @param v the value to look for
* @return the value in the cache or the value passed
*/
static Value cache(Value v) {
if (SysProperties.OBJECT_CACHE) {
int hash = v.hashCode();
if (softCache == null) {
softCache = new SoftReference<Value[]>(null);
}
Value[] cache = softCache.get();
if (cache == null) {
cache = new Value[SysProperties.OBJECT_CACHE_SIZE];
softCache = new SoftReference<Value[]>(cache);
}
int index = hash & (SysProperties.OBJECT_CACHE_SIZE - 1);
Value cached = cache[index];
if (cached != null) {
if (cached.getType() == v.getType() && v.equals(cached)) {
// cacheHit++;
return cached;
}
}
// cacheMiss++;
// cache[cacheCleaner] = null;
// cacheCleaner = (cacheCleaner + 1) &
// (Constants.OBJECT_CACHE_SIZE - 1);
cache[index] = v;
}
return v;
}
/**
* Clear the value cache. Used for testing.
*/
public static void clearCache() {
softCache = null;
}
public Boolean getBoolean() {
return ((ValueBoolean) convertTo(Value.BOOLEAN)).getBoolean();
}
public Date getDate() {
return ((ValueDate) convertTo(Value.DATE)).getDate();
}
public Time getTime() {
return ((ValueTime) convertTo(Value.TIME)).getTime();
}
public Timestamp getTimestamp() {
return ((ValueTimestamp) convertTo(Value.TIMESTAMP)).getTimestamp();
}
public byte[] getBytes() {
return ((ValueBytes) convertTo(Value.BYTES)).getBytes();
}
public byte[] getBytesNoCopy() {
return ((ValueBytes) convertTo(Value.BYTES)).getBytesNoCopy();
}
public byte getByte() {
return ((ValueByte) convertTo(Value.BYTE)).getByte();
}
public short getShort() {
return ((ValueShort) convertTo(Value.SHORT)).getShort();
}
public BigDecimal getBigDecimal() {
return ((ValueDecimal) convertTo(Value.DECIMAL)).getBigDecimal();
}
public double getDouble() {
return ((ValueDouble) convertTo(Value.DOUBLE)).getDouble();
}
public float getFloat() {
return ((ValueFloat) convertTo(Value.FLOAT)).getFloat();
}
public int getInt() {
return ((ValueInt) convertTo(Value.INT)).getInt();
}
public long getLong() {
return ((ValueLong) convertTo(Value.LONG)).getLong();
}
public InputStream getInputStream() {
return new ByteArrayInputStream(getBytesNoCopy());
}
public Reader getReader() {
return new StringReader(getString());
}
/**
* Add a value and return the result.
*
* @param v the value to add
* @return the result
*/
public Value add(Value v) {
throw throwUnsupportedExceptionForType("+");
}
public int getSignum() {
throw throwUnsupportedExceptionForType("SIGNUM");
}
/**
* Return -value if this value support arithmetic operations.
*
* @return the negative
*/
public Value negate() {
throw throwUnsupportedExceptionForType("NEG");
}
/**
* Subtract a value and return the result.
*
* @param v the value to subtract
* @return the result
*/
public Value subtract(Value v) {
throw throwUnsupportedExceptionForType("-");
}
/**
* Divide by a value and return the result.
*
* @param v the value to divide by
* @return the result
*/
public Value divide(Value v) {
throw throwUnsupportedExceptionForType("/");
}
/**
* Multiply with a value and return the result.
*
* @param v the value to multiply with
* @return the result
*/
public Value multiply(Value v) {
throw throwUnsupportedExceptionForType("*");
}
/**
* Take the modulus with a value and return the result.
*
* @param v the value to take the modulus with
* @return the result
*/
public Value modulus(Value v) {
throw throwUnsupportedExceptionForType("%");
}
/**
* Compare a value to the specified type.
*
* @param targetType the type of the returned value
* @return the converted value
*/
public Value convertTo(int targetType) {
// converting NULL is done in ValueNull
// converting BLOB to CLOB and vice versa is done in ValueLob
if (getType() == targetType) {
return this;
}
try {
// decimal conversion
switch (targetType) {
case BOOLEAN: {
switch (getType()) {
case BYTE:
case SHORT:
case INT:
case LONG:
case DECIMAL:
case DOUBLE:
case FLOAT:
return ValueBoolean.get(getSignum() != 0);
case TIME:
case DATE:
case TIMESTAMP:
case TIMESTAMP_TZ:
case BYTES:
case JAVA_OBJECT:
case UUID:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case BYTE: {
switch (getType()) {
case BOOLEAN:
return ValueByte.get(getBoolean().booleanValue() ? (byte) 1 : (byte) 0);
case SHORT:
return ValueByte.get(convertToByte(getShort()));
case INT:
return ValueByte.get(convertToByte(getInt()));
case LONG:
return ValueByte.get(convertToByte(getLong()));
case DECIMAL:
return ValueByte.get(convertToByte(convertToLong(getBigDecimal())));
case DOUBLE:
return ValueByte.get(convertToByte(convertToLong(getDouble())));
case FLOAT:
return ValueByte.get(convertToByte(convertToLong(getFloat())));
case BYTES:
return ValueByte.get((byte) Integer.parseInt(getString(), 16));
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case SHORT: {
switch (getType()) {
case BOOLEAN:
return ValueShort.get(getBoolean().booleanValue() ? (short) 1 : (short) 0);
case BYTE:
return ValueShort.get(getByte());
case INT:
return ValueShort.get(convertToShort(getInt()));
case LONG:
return ValueShort.get(convertToShort(getLong()));
case DECIMAL:
return ValueShort.get(convertToShort(convertToLong(getBigDecimal())));
case DOUBLE:
return ValueShort.get(convertToShort(convertToLong(getDouble())));
case FLOAT:
return ValueShort.get(convertToShort(convertToLong(getFloat())));
case BYTES:
return ValueShort.get((short) Integer.parseInt(getString(), 16));
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case INT: {
switch (getType()) {
case BOOLEAN:
return ValueInt.get(getBoolean().booleanValue() ? 1 : 0);
case BYTE:
return ValueInt.get(getByte());
case SHORT:
return ValueInt.get(getShort());
case LONG:
return ValueInt.get(convertToInt(getLong()));
case DECIMAL:
return ValueInt.get(convertToInt(convertToLong(getBigDecimal())));
case DOUBLE:
return ValueInt.get(convertToInt(convertToLong(getDouble())));
case FLOAT:
return ValueInt.get(convertToInt(convertToLong(getFloat())));
case BYTES:
return ValueInt.get((int) Long.parseLong(getString(), 16));
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case LONG: {
switch (getType()) {
case BOOLEAN:
return ValueLong.get(getBoolean().booleanValue() ? 1 : 0);
case BYTE:
return ValueLong.get(getByte());
case SHORT:
return ValueLong.get(getShort());
case INT:
return ValueLong.get(getInt());
case DECIMAL:
return ValueLong.get(convertToLong(getBigDecimal()));
case DOUBLE:
return ValueLong.get(convertToLong(getDouble()));
case FLOAT:
return ValueLong.get(convertToLong(getFloat()));
case BYTES: {
// parseLong doesn't work for ffffffffffffffff
byte[] d = getBytes();
if (d.length == 8) {
return ValueLong.get(Utils.readLong(d, 0));
}
return ValueLong.get(Long.parseLong(getString(), 16));
}
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case DECIMAL: {
switch (getType()) {
case BOOLEAN:
return ValueDecimal.get(BigDecimal.valueOf(
getBoolean().booleanValue() ? 1 : 0));
case BYTE:
return ValueDecimal.get(BigDecimal.valueOf(getByte()));
case SHORT:
return ValueDecimal.get(BigDecimal.valueOf(getShort()));
case INT:
return ValueDecimal.get(BigDecimal.valueOf(getInt()));
case LONG:
return ValueDecimal.get(BigDecimal.valueOf(getLong()));
case DOUBLE: {
double d = getDouble();
if (Double.isInfinite(d) || Double.isNaN(d)) {
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, "" + d);
}
return ValueDecimal.get(BigDecimal.valueOf(d));
}
case FLOAT: {
float f = getFloat();
if (Float.isInfinite(f) || Float.isNaN(f)) {
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, "" + f);
}
// better rounding behavior than BigDecimal.valueOf(f)
return ValueDecimal.get(new BigDecimal(Float.toString(f)));
}
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case DOUBLE: {
switch (getType()) {
case BOOLEAN:
return ValueDouble.get(getBoolean().booleanValue() ? 1 : 0);
case BYTE:
return ValueDouble.get(getByte());
case SHORT:
return ValueDouble.get(getShort());
case INT:
return ValueDouble.get(getInt());
case LONG:
return ValueDouble.get(getLong());
case DECIMAL:
return ValueDouble.get(getBigDecimal().doubleValue());
case FLOAT:
return ValueDouble.get(getFloat());
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case FLOAT: {
switch (getType()) {
case BOOLEAN:
return ValueFloat.get(getBoolean().booleanValue() ? 1 : 0);
case BYTE:
return ValueFloat.get(getByte());
case SHORT:
return ValueFloat.get(getShort());
case INT:
return ValueFloat.get(getInt());
case LONG:
return ValueFloat.get(getLong());
case DECIMAL:
return ValueFloat.get(getBigDecimal().floatValue());
case DOUBLE:
return ValueFloat.get((float) getDouble());
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case DATE: {
switch (getType()) {
case TIME:
// because the time has set the date to 1970-01-01,
// this will be the result
return ValueDate.fromDateValue(
DateTimeUtils.dateValue(1970, 1, 1));
case TIMESTAMP:
return ValueDate.fromDateValue(
((ValueTimestamp) this).getDateValue());
case TIMESTAMP_TZ:
return ValueDate.fromDateValue(
((ValueTimestampTimeZone) this).getDateValue());
}
break;
}
case TIME: {
switch (getType()) {
case DATE:
// need to normalize the year, month and day because a date
// has the time set to 0, the result will be 0
return ValueTime.fromNanos(0);
case TIMESTAMP:
return ValueTime.fromNanos(
((ValueTimestamp) this).getTimeNanos());
case TIMESTAMP_TZ:
return ValueTime.fromNanos(
((ValueTimestampTimeZone) this).getTimeNanos());
}
break;
}
case TIMESTAMP: {
switch (getType()) {
case TIME:
return DateTimeUtils.normalizeTimestamp(
0, ((ValueTime) this).getNanos());
case DATE:
return ValueTimestamp.fromDateValueAndNanos(
((ValueDate) this).getDateValue(), 0);
case TIMESTAMP_TZ:
return ValueTimestamp.fromDateValueAndNanos(
((ValueTimestampTimeZone) this).getDateValue(),
((ValueTimestampTimeZone) this).getTimeNanos());
}
break;
}
case BYTES: {
switch (getType()) {
case JAVA_OBJECT:
case BLOB:
return ValueBytes.getNoCopy(getBytesNoCopy());
case UUID:
case GEOMETRY:
return ValueBytes.getNoCopy(getBytes());
case BYTE:
return ValueBytes.getNoCopy(new byte[]{getByte()});
case SHORT: {
int x = getShort();
return ValueBytes.getNoCopy(new byte[]{
(byte) (x >> 8),
(byte) x
});
}
case INT: {
int x = getInt();
return ValueBytes.getNoCopy(new byte[]{
(byte) (x >> 24),
(byte) (x >> 16),
(byte) (x >> 8),
(byte) x
});
}
case LONG: {
long x = getLong();
return ValueBytes.getNoCopy(new byte[]{
(byte) (x >> 56),
(byte) (x >> 48),
(byte) (x >> 40),
(byte) (x >> 32),
(byte) (x >> 24),
(byte) (x >> 16),
(byte) (x >> 8),
(byte) x
});
}
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case JAVA_OBJECT: {
switch (getType()) {
case BYTES:
case BLOB:
return ValueJavaObject.getNoCopy(
null, getBytesNoCopy(), getDataHandler());
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case BLOB: {
switch (getType()) {
case BYTES:
return ValueLobDb.createSmallLob(
Value.BLOB, getBytesNoCopy());
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case UUID: {
switch (getType()) {
case BYTES:
return ValueUuid.get(getBytesNoCopy());
case JAVA_OBJECT:
Object object = JdbcUtils.deserialize(getBytesNoCopy(),
getDataHandler());
if (object instanceof java.util.UUID) {
java.util.UUID uuid = (java.util.UUID) object;
return ValueUuid.get(uuid.getMostSignificantBits(),
uuid.getLeastSignificantBits());
}
throw DbException.get(ErrorCode.DATA_CONVERSION_ERROR_1, getString());
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
case GEOMETRY: {
switch (getType()) {
case BYTES:
return ValueGeometry.get(getBytesNoCopy());
case JAVA_OBJECT:
Object object = JdbcUtils.deserialize(getBytesNoCopy(), getDataHandler());
if (DataType.isGeometry(object)) {
return ValueGeometry.getFromGeometry(object);
}
case TIMESTAMP_TZ:
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, getString());
}
break;
}
}
// conversion by parsing the string value
String s = getString();
switch (targetType) {
case NULL:
return ValueNull.INSTANCE;
case BOOLEAN: {
if (s.equalsIgnoreCase("true") ||
s.equalsIgnoreCase("t") ||
s.equalsIgnoreCase("yes") ||
s.equalsIgnoreCase("y")) {
return ValueBoolean.get(true);
} else if (s.equalsIgnoreCase("false") ||
s.equalsIgnoreCase("f") ||
s.equalsIgnoreCase("no") ||
s.equalsIgnoreCase("n")) {
return ValueBoolean.get(false);
} else {
// convert to a number, and if it is not 0 then it is true
return ValueBoolean.get(new BigDecimal(s).signum() != 0);
}
}
case BYTE:
return ValueByte.get(Byte.parseByte(s.trim()));
case SHORT:
return ValueShort.get(Short.parseShort(s.trim()));
case INT:
return ValueInt.get(Integer.parseInt(s.trim()));
case LONG:
return ValueLong.get(Long.parseLong(s.trim()));
case DECIMAL:
return ValueDecimal.get(new BigDecimal(s.trim()));
case TIME:
return ValueTime.parse(s.trim());
case DATE:
return ValueDate.parse(s.trim());
case TIMESTAMP:
return ValueTimestamp.parse(s.trim());
case TIMESTAMP_TZ:
return ValueTimestampTimeZone.parse(s.trim());
case BYTES:
return ValueBytes.getNoCopy(
StringUtils.convertHexToBytes(s.trim()));
case JAVA_OBJECT:
return ValueJavaObject.getNoCopy(null,
StringUtils.convertHexToBytes(s.trim()), getDataHandler());
case STRING:
return ValueString.get(s);
case STRING_IGNORECASE:
return ValueStringIgnoreCase.get(s);
case STRING_FIXED:
return ValueStringFixed.get(s);
case DOUBLE:
return ValueDouble.get(Double.parseDouble(s.trim()));
case FLOAT:
return ValueFloat.get(Float.parseFloat(s.trim()));
case CLOB:
return ValueLobDb.createSmallLob(
CLOB, s.getBytes(Constants.UTF8));
case BLOB:
return ValueLobDb.createSmallLob(
BLOB, StringUtils.convertHexToBytes(s.trim()));
case ARRAY:
return ValueArray.get(new Value[]{ValueString.get(s)});
case RESULT_SET: {
SimpleResultSet rs = new SimpleResultSet();
rs.setAutoClose(false);
rs.addColumn("X", Types.VARCHAR, s.length(), 0);
rs.addRow(s);
return ValueResultSet.get(rs);
}
case UUID:
return ValueUuid.get(s);
case GEOMETRY:
return ValueGeometry.get(s);
default:
throw DbException.throwInternalError("type=" + targetType);
}
} catch (NumberFormatException e) {
throw DbException.get(
ErrorCode.DATA_CONVERSION_ERROR_1, e, getString());
}
}
/**
* Compare this value against another value given that the values are of the
* same data type.
*
* @param v the other value
* @param mode the compare mode
* @return 0 if both values are equal, -1 if the other value is smaller, and
* 1 otherwise
*/
public final int compareTypeSafe(Value v, CompareMode mode) {
if (this == v) {
return 0;
} else if (this == ValueNull.INSTANCE) {
return -1;
} else if (v == ValueNull.INSTANCE) {
return 1;
}
return compareSecure(v, mode);
}
/**
* Compare this value against another value using the specified compare
* mode.
*
* @param v the other value
* @param mode the compare mode
* @return 0 if both values are equal, -1 if the other value is smaller, and
* 1 otherwise
*/
public final int compareTo(Value v, CompareMode mode) {
if (this == v) {
return 0;
}
if (this == ValueNull.INSTANCE) {
return v == ValueNull.INSTANCE ? 0 : -1;
} else if (v == ValueNull.INSTANCE) {
return 1;
}
if (getType() == v.getType()) {
return compareSecure(v, mode);
}
int t2 = Value.getHigherOrder(getType(), v.getType());
return convertTo(t2).compareSecure(v.convertTo(t2), mode);
}
public int getScale() {
//ValueDecimal、ValueDouble、ValueFloat、ValueTimestamp覆盖了，但是ValueDouble、ValueFloat还是返回0
return 0;
}
/**
* Convert the scale.
*
* @param onlyToSmallerScale if the scale should not reduced
* @param targetScale the requested scale
* @return the value
*/
public Value convertScale(boolean onlyToSmallerScale, int targetScale) {
return this;
}
/**
* Convert the precision to the requested value. The precision of the
* returned value may be somewhat larger than requested, because values with
* a fixed precision are not truncated.
*
* @param precision the new precision
* @param force true if losing numeric precision is allowed
* @return the new value
*/
public Value convertPrecision(long precision, boolean force) {
return this;
}
private static byte convertToByte(long x) {
if (x > Byte.MAX_VALUE || x < Byte.MIN_VALUE) {
throw DbException.get(
ErrorCode.NUMERIC_VALUE_OUT_OF_RANGE_1, Long.toString(x));
}
return (byte) x;
}
private static short convertToShort(long x) {
if (x > Short.MAX_VALUE || x < Short.MIN_VALUE) {
throw DbException.get(
ErrorCode.NUMERIC_VALUE_OUT_OF_RANGE_1, Long.toString(x));
}
return (short) x;
}
private static int convertToInt(long x) {
if (x > Integer.MAX_VALUE || x < Integer.MIN_VALUE) {
throw DbException.get(
ErrorCode.NUMERIC_VALUE_OUT_OF_RANGE_1, Long.toString(x));
}
return (int) x;
}
private static long convertToLong(double x) {
if (x > Long.MAX_VALUE || x < Long.MIN_VALUE) {
// TODO document that +Infinity, -Infinity throw an exception and
// NaN returns 0
throw DbException.get(
ErrorCode.NUMERIC_VALUE_OUT_OF_RANGE_1, Double.toString(x));
}
return Math.round(x);
}
private static long convertToLong(BigDecimal x) {
if (x.compareTo(MAX_LONG_DECIMAL) > 0 ||
x.compareTo(Value.MIN_LONG_DECIMAL) < 0) {
throw DbException.get(
ErrorCode.NUMERIC_VALUE_OUT_OF_RANGE_1, x.toString());
}
return x.setScale(0, BigDecimal.ROUND_HALF_UP).longValue();
}
/**
* Copy a large value, to be used in the given table. For values that are
* kept fully in memory this method has no effect.
*
* @param handler the data handler
* @param tableId the table where this object is used
* @return the new value or itself
*/
public Value copy(DataHandler handler, int tableId) { //只对ValueLob、ValueLobDb有用
return this;
}
/**
* Check if this value is linked to a specific table. For values that are
* kept fully in memory, this method returns false.
*
* @return true if it is
*/
public boolean isLinkedToTable() { //只对ValueLob、ValueLobDb有用
return false;
}
/**
* Remove the underlying resource, if any. For values that are kept fully in
* memory this method has no effect.
*/
public void remove() { //只对ValueLob、ValueLobDb有用
// nothing to do
}
/**
* Check if the precision is smaller or equal than the given precision.
*
* @param precision the maximum precision
* @return true if the precision of this value is smaller or equal to the
* given precision
*/
public boolean checkPrecision(long precision) {
return getPrecision() <= precision;
}
/**
* Get a medium size SQL expression for debugging or tracing. If the
* precision is too large, only a subset of the value is returned.
*
* @return the SQL expression
*/
public String getTraceSQL() {
return getSQL();
}
@Override
public String toString() {
return getTraceSQL();
}
/**
* Throw the exception that the feature is not support for the given data
* type.
*
* @param op the operation
* @return never returns normally
* @throws DbException the exception
*/
protected DbException throwUnsupportedExceptionForType(String op) {
throw DbException.getUnsupportedException(
DataType.getDataType(getType()).name + " " + op);
}
/**
* Get the table (only for LOB object).
*
* @return the table id
*/
public int getTableId() { //只对ValueLob、ValueLobDb有用
return 0;
}
/**
* Get the byte array.
*
* @return the byte array
*/
public byte[] getSmall() { //只对ValueLob、ValueLobDb有用
return null;
}
/**
* Copy this value to a temporary file if necessary.
*
* @return the new value
*/
public Value copyToTemp() { //只对ValueLob、ValueLobDb有用
return this;
}
/**
* Create an independent copy of this value if needed, that will be bound to
* a result. If the original row is removed, this copy is still readable.
*
* @return the value (this for small objects)
*/
public Value copyToResult() {
return this;
}
public ResultSet getResultSet() {
SimpleResultSet rs = new SimpleResultSet();
rs.setAutoClose(false);
rs.addColumn("X", DataType.convertTypeToSQLType(getType()),
MathUtils.convertLongToInt(getPrecision()), getScale());
rs.addRow(getObject());
return rs;
}
/**
* Return the data handler for the values that support it
* (actually only Java objects).
* @return the data handler
*/
protected DataHandler getDataHandler() {
return null;
}
/**
* A "binary large object".
*/
public interface ValueClob { //只对ValueLobDb有用
// this is a marker interface
}
/**
* A "character large object".
*/
public interface ValueBlob { //只对ValueLobDb有用
// this is a marker interface
}
}