/**
* Creates a string in a specfied character set.
*
* @param value String constant, must not be null
* @param charsetName Name of the character set, may be null
* @param collation Collation, may be null
* @throws IllegalCharsetNameException If the given charset name is illegal
* @throws UnsupportedCharsetException If no support for the named charset is available in this
* instance of the Java virtual machine
* @throws RuntimeException If the given value cannot be represented in the given charset
*/
public NlsString(String value, String charsetName, SqlCollation collation) {
assert value != null;
if (null != charsetName) {
charsetName = charsetName.toUpperCase();
this.charsetName = charsetName;
String javaCharsetName = SqlUtil.translateCharacterSetName(charsetName);
if (javaCharsetName == null) {
throw new UnsupportedCharsetException(charsetName);
}
this.charset = Charset.forName(javaCharsetName);
CharsetEncoder encoder = charset.newEncoder();
// dry run to see if encoding hits any problems
try {
encoder.encode(CharBuffer.wrap(value));
} catch (CharacterCodingException ex) {
throw RESOURCE.charsetEncoding(value, javaCharsetName).ex();
}
} else {
this.charsetName = null;
this.charset = null;
}
this.collation = collation;
this.value = value;
}
/**
* Creates a literal like X'ABAB' from an array of bytes.
*
* @param bytes Contents of binary literal
* @param pos Parser position
* @return Binary string literal
*/
public static SqlBinaryStringLiteral createBinaryString(byte[] bytes, SqlParserPos pos) {
BitString bits;
try {
bits = BitString.createFromBytes(bytes);
} catch (NumberFormatException e) {
throw SqlUtil.newContextException(pos, RESOURCE.binaryLiteralInvalid());
}
return new SqlBinaryStringLiteral(bits, pos);
}
/**
* Transforms this literal (which must be of type character) into a new one in which 4-digit
* Unicode escape sequences have been replaced with the corresponding Unicode characters.
*
* @param unicodeEscapeChar escape character (e.g. backslash) for Unicode numeric sequences; 0
* implies no transformation
* @return transformed literal
*/
public SqlLiteral unescapeUnicode(char unicodeEscapeChar) {
if (unicodeEscapeChar == 0) {
return this;
}
assert SqlTypeUtil.inCharFamily(getTypeName());
NlsString ns = (NlsString) value;
String s = ns.getValue();
StringBuilder sb = new StringBuilder();
int n = s.length();
for (int i = 0; i < n; ++i) {
char c = s.charAt(i);
if (c == unicodeEscapeChar) {
if (n > (i + 1)) {
if (s.charAt(i + 1) == unicodeEscapeChar) {
sb.append(unicodeEscapeChar);
++i;
continue;
}
}
if ((i + 5) > n) {
throw SqlUtil.newContextException(
getParserPosition(), RESOURCE.unicodeEscapeMalformed(i));
}
final String u = s.substring(i + 1, i + 5);
final int v;
try {
v = Integer.parseInt(u, 16);
} catch (NumberFormatException ex) {
throw SqlUtil.newContextException(
getParserPosition(), RESOURCE.unicodeEscapeMalformed(i));
}
sb.append((char) (v & 0xFFFF));
// skip hexits
i += 4;
} else {
sb.append(c);
}
}
ns = new NlsString(sb.toString(), ns.getCharsetName(), ns.getCollation());
return new SqlCharStringLiteral(ns, getParserPosition());
}
/** @pre SqlTypeUtil.sameNamedType(argTypes[0], (argTypes[1])) */
public RelDataType inferReturnType(SqlOperatorBinding opBinding) {
final RelDataType argType0 = opBinding.getOperandType(0);
final RelDataType argType1 = opBinding.getOperandType(1);
if (!(SqlTypeUtil.inCharOrBinaryFamilies(argType0)
&& SqlTypeUtil.inCharOrBinaryFamilies(argType1))) {
Util.pre(
SqlTypeUtil.sameNamedType(argType0, argType1),
"SqlTypeUtil.sameNamedType(argTypes[0], argTypes[1])");
}
SqlCollation pickedCollation = null;
if (SqlTypeUtil.inCharFamily(argType0)) {
if (!SqlTypeUtil.isCharTypeComparable(opBinding.collectOperandTypes().subList(0, 2))) {
throw opBinding.newError(
RESOURCE.typeNotComparable(
argType0.getFullTypeString(), argType1.getFullTypeString()));
}
pickedCollation =
SqlCollation.getCoercibilityDyadicOperator(
argType0.getCollation(), argType1.getCollation());
assert null != pickedCollation;
}
// Determine whether result is variable-length
SqlTypeName typeName = argType0.getSqlTypeName();
if (SqlTypeUtil.isBoundedVariableWidth(argType1)) {
typeName = argType1.getSqlTypeName();
}
RelDataType ret;
ret =
opBinding
.getTypeFactory()
.createSqlType(typeName, argType0.getPrecision() + argType1.getPrecision());
if (null != pickedCollation) {
RelDataType pickedType;
if (argType0.getCollation().equals(pickedCollation)) {
pickedType = argType0;
} else if (argType1.getCollation().equals(pickedCollation)) {
pickedType = argType1;
} else {
throw Util.newInternal("should never come here");
}
ret =
opBinding
.getTypeFactory()
.createTypeWithCharsetAndCollation(
ret, pickedType.getCharset(), pickedType.getCollation());
}
return ret;
}
/**
* Returns the long value of this literal.
*
* @param exact Whether the value has to be exact. If true, and the literal is a fraction (e.g.
* 3.14), throws. If false, discards the fractional part of the value.
* @return Long value of this literal
*/
public long longValue(boolean exact) {
switch (typeName) {
case DECIMAL:
case DOUBLE:
BigDecimal bd = (BigDecimal) value;
if (exact) {
try {
return bd.longValueExact();
} catch (ArithmeticException e) {
throw SqlUtil.newContextException(
getParserPosition(), RESOURCE.numberLiteralOutOfRange(bd.toString()));
}
} else {
return bd.longValue();
}
default:
throw Util.unexpected(typeName);
}
}
