com.sap.cds.jdbc.sqlite.functions.LikeRegexpFunction Maven / Gradle / Ivy
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/*******************************************************************
* © 2023 SAP SE or an SAP affiliate company. All rights reserved. *
*******************************************************************/
package com.sap.cds.jdbc.sqlite.functions;
import java.sql.SQLException;
import java.util.regex.Pattern;
import org.sqlite.Function;
/**
* Emulate SQL standard implementation as LIKE_REGEX(field, pattern, flags).
*/
public class LikeRegexpFunction extends Function {
@Override
protected void xFunc() throws SQLException {
try {
String text = value_text(0);
String pattern = value_text(1);
String flags = value_text(2);
// Emulate the way H2 does that. The 'c' is not supported.
int arguments = Pattern.UNICODE_CASE;
for (int i = 0; i < flags.length(); i++) {
switch (flags.charAt(i)) {
case 'i' -> arguments |= Pattern.CASE_INSENSITIVE;
case 'm' -> arguments |= Pattern.MULTILINE;
case 'n' -> arguments |= Pattern.DOTALL;
default -> throw new IllegalArgumentException("Unsupported flag: " + flags.charAt(i));
}
}
boolean found = Pattern.compile(pattern, arguments).matcher(text).find();
result(found ? 1 : 0);
} catch (Exception e) {
error(e.getMessage());
}
}
}