com.sap.cds.impl.sql.SQLHelper Maven / Gradle / Ivy
/************************************************************************
* © 2019-2022 SAP SE or an SAP affiliate company. All rights reserved. *
************************************************************************/
package com.sap.cds.impl.sql;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import com.sap.cds.impl.PreparedCqnStmt.DataParam;
import com.sap.cds.reflect.CdsBaseType;
import com.sap.cds.reflect.CdsElement;
import com.sap.cds.reflect.CdsSimpleType;
import com.sap.cds.reflect.CdsType;
public class SQLHelper {
private static final char DQ = '\"';
private static final char SQ = '\'';
private SQLHelper() {
}
public static String commaSeparated(Stream stream) {
return stream.collect(Collectors.joining(", ", "(", ")"));
}
public static DataParam param(String path, CdsElement element) {
CdsType type = element.getType();
CdsBaseType baseType = type.isSimple() ? type.as(CdsSimpleType.class).getType() : null;
return new DataParam(path, baseType);
}
public static String delimited(String undelimited) {
return DQ + prefix(undelimited, DQ, DQ) + DQ;
}
public static String literal(String text) {
return text == null ? "NULL" : SQ + prefix(text, SQ, SQ) + SQ;
}
public static String escapeLikePattern(char escapeChar, String text) {
text = prefix(text, escapeChar, '_');
text = prefix(text, escapeChar, '%');
return text;
}
private static String prefix(String text, char escapeChar, char toBeEscaped) {
for (int i = 0; i < text.length(); i++) {
if (text.charAt(i) == toBeEscaped) {
return prefixFrom(text, i, escapeChar, text.length(), toBeEscaped);
}
}
return text;
}
private static String prefixFrom(String text, int from, char escapeChar, int length, char toBeEscaped) {
char[] buffer = new char[length * 2];
text.getChars(0, from, buffer, 0);
int j = from;
for (int i = from; i < length; i++) {
char c = text.charAt(i);
if (c == toBeEscaped) {
buffer[j++] = escapeChar;
}
buffer[j++] = c;
}
return String.copyValueOf(buffer, 0, j);
}
}