private Expression readTerm() {
Expression r;
switch (currentTokenType) {
case AT:
read();
r = new Variable(session, readAliasIdentifier());
if (readIf(":=")) {
Expression value = readExpression();
Function function = Function.getFunction(database, "SET");
function.setParameter(0, r);
function.setParameter(1, value);
r = function;
}
break;
case PARAMETER:
// there must be no space between ? and the number
boolean indexed = Character.isDigit(sqlCommandChars[parseIndex]);
read();
Parameter p;
if (indexed && currentTokenType == VALUE && currentValue.getType() == Value.INT) {
if (indexedParameterList == null) {
if (parameters == null) {
// this can occur when parsing expressions only (for example check constraints)
throw getSyntaxError();
} else if (parameters.size() > 0) {
throw DbException.get(ErrorCode.CANNOT_MIX_INDEXED_AND_UNINDEXED_PARAMS);
}
indexedParameterList = New.arrayList();
}
int index = currentValue.getInt() - 1;
if (index < 0 || index >= Constants.MAX_PARAMETER_INDEX) {
throw DbException.getInvalidValueException("parameter index", index);
}
if (indexedParameterList.size() <= index) {
indexedParameterList.ensureCapacity(index + 1);
while (indexedParameterList.size() <= index) {
indexedParameterList.add(null);
}
}
p = indexedParameterList.get(index);
if (p == null) {
p = new Parameter(index);
indexedParameterList.set(index, p);
}
read();
} else {
if (indexedParameterList != null) {
throw DbException.get(ErrorCode.CANNOT_MIX_INDEXED_AND_UNINDEXED_PARAMS);
}
p = new Parameter(parameters.size());
}
parameters.add(p);
r = p;
break;
case KEYWORD:
if (isToken("SELECT") || isToken("FROM")) {
Query query = parseSelect();
r = new Subquery(query);
} else {
throw getSyntaxError();
}
break;
case IDENTIFIER:
String name = currentToken;
if (currentTokenQuoted) {
read();
if (readIf("(")) {
r = readFunction(null, name);
} else if (readIf(".")) {
r = readTermObjectDot(name);
} else {
r = new ExpressionColumn(database, null, null, name);
}
} else {
read();
if (readIf(".")) {
r = readTermObjectDot(name);
} else if (equalsToken("CASE", name)) {
// CASE must be processed before (,
// otherwise CASE(3) would be a function call, which it is
// not
if (isToken("WHEN")) {
r = readWhen(null);
} else {
Expression left = readExpression();
r = readWhen(left);
}
} else if (readIf("(")) {
r = readFunction(null, name);
} else if (equalsToken("CURRENT_USER", name)) {
r = readFunctionWithoutParameters("USER");
} else if (equalsToken("CURRENT", name)) {
if (readIf("TIMESTAMP")) {
r = readFunctionWithoutParameters("CURRENT_TIMESTAMP");
} else if (readIf("TIME")) {
r = readFunctionWithoutParameters("CURRENT_TIME");
} else if (readIf("DATE")) {
r = readFunctionWithoutParameters("CURRENT_DATE");
} else {
r = new ExpressionColumn(database, null, null, name);
}
} else if (equalsToken("NEXT", name) && readIf("VALUE")) {
read("FOR");
Sequence sequence = readSequence();
r = new SequenceValue(sequence);
} else if (currentTokenType == VALUE && currentValue.getType() == Value.STRING) {
if (equalsToken("DATE", name)) {
String date = currentValue.getString();
read();
r = ValueExpression.get(ValueDate.parse(date));
} else if (equalsToken("TIME", name)) {
String time = currentValue.getString();
read();
r = ValueExpression.get(ValueTime.parse(time));
} else if (equalsToken("TIMESTAMP", name)) {
String timestamp = currentValue.getString();
read();
r = ValueExpression.get(ValueTimestamp.parse(timestamp));
} else if (equalsToken("X", name)) {
read();
byte[] buffer = StringUtils.convertHexToBytes(currentValue.getString());
r = ValueExpression.get(ValueBytes.getNoCopy(buffer));
} else if (equalsToken("E", name)) {
String text = currentValue.getString();
// the PostgreSQL ODBC driver uses
// LIKE E'PROJECT\\_DATA' instead of LIKE 'PROJECT\_DATA'
// N: SQL-92 "National Language" strings
text = StringUtils.replaceAll(text, "\\\\", "\\");
read();
r = ValueExpression.get(ValueString.get(text));
} else if (equalsToken("N", name)) {
// SQL-92 "National Language" strings
String text = currentValue.getString();
read();
r = ValueExpression.get(ValueString.get(text));
} else {
r = new ExpressionColumn(database, null, null, name);
}
} else {
r = new ExpressionColumn(database, null, null, name);
}
}
break;
case MINUS:
read();
if (currentTokenType == VALUE) {
r = ValueExpression.get(currentValue.negate());
if (r.getType() == Value.LONG && r.getValue(session).getLong() == Integer.MIN_VALUE) {
// convert Integer.MIN_VALUE to type 'int'
// (Integer.MAX_VALUE+1 is of type 'long')
r = ValueExpression.get(ValueInt.get(Integer.MIN_VALUE));
} else if (r.getType() == Value.DECIMAL && r.getValue(session).getBigDecimal().compareTo(ValueLong.MIN_BD) == 0) {
// convert Long.MIN_VALUE to type 'long'
// (Long.MAX_VALUE+1 is of type 'decimal')
r = ValueExpression.get(ValueLong.get(Long.MIN_VALUE));
}
read();
} else {
r = new Operation(Operation.NEGATE, readTerm(), null);
}
break;
case PLUS:
read();
r = readTerm();
break;
case OPEN:
read();
if (readIf(")")) {
r = new ExpressionList(new Expression[0]);
} else {
r = readExpression();
if (readIf(",")) {
ArrayList<Expression> list = New.arrayList();
list.add(r);
while (!readIf(")")) {
r = readExpression();
list.add(r);
if (!readIf(",")) {
read(")");
break;
}
}
Expression[] array = new Expression[list.size()];
list.toArray(array);
r = new ExpressionList(array);
} else {
read(")");
}
}
break;
case TRUE:
read();
r = ValueExpression.get(ValueBoolean.get(true));
break;
case FALSE:
read();
r = ValueExpression.get(ValueBoolean.get(false));
break;
case CURRENT_TIME:
read();
r = readFunctionWithoutParameters("CURRENT_TIME");
break;
case CURRENT_DATE:
read();
r = readFunctionWithoutParameters("CURRENT_DATE");
break;
case CURRENT_TIMESTAMP: {
Function function = Function.getFunction(database, "CURRENT_TIMESTAMP");
read();
if (readIf("(")) {
if (!readIf(")")) {
function.setParameter(0, readExpression());
read(")");
}
}
function.doneWithParameters();
r = function;
break;
}
case ROWNUM:
read();
if (readIf("(")) {
read(")");
}
r = new Rownum(currentSelect == null ? currentPrepared : currentSelect);
break;
case NULL:
read();
r = ValueExpression.getNull();
break;
case VALUE:
r = ValueExpression.get(currentValue);
read();
break;
default:
throw getSyntaxError();
}
if (readIf("[")) {
Function function = Function.getFunction(database, "ARRAY_GET");
function.setParameter(0, r);
r = readExpression();
r = new Operation(Operation.PLUS, r, ValueExpression.get(ValueInt.get(1)));
function.setParameter(1, r);
r = function;
read("]");
}
if (readIf("::")) {
// PostgreSQL compatibility
if (readIf("REGCLASS")) {
FunctionAlias f = findFunctionAlias(Constants.SCHEMA_MAIN, "PG_GET_OID");
if (f == null) {
throw getSyntaxError();
}
Expression[] args = { r };
JavaFunction func = new JavaFunction(f, args);
r = func;
} else {
Column col = parseColumnWithType(null);
Function function = Function.getFunction(database, "CAST");
function.setDataType(col);
function.setParameter(0, r);
r = function;
}
}
return r;
}