Support for "NOT LIKE" and "NOT SIMILAR TO"

The parser and StringMatchOperator class only supported "LIKE" and
"SIMILAR TO", not the inverse.  Now this is fixed.

log4j2.properties

@@ -17,7 +17,7 @@ appender.console.filter.threshold.level = debug
 appender.rolling.type = RollingFile
 appender.rolling.name = RollingFile
 appender.rolling.fileName = ${filename}
-appender.rolling.filePattern = ./nanodb-%d{MMddyy-HHmmss}-%i.log
+appender.rolling.filePattern = ./nanodb-%i.log
 appender.rolling.layout.type = PatternLayout
 appender.rolling.layout.pattern = %d %p %C{1.} [%t] %m%n
 appender.rolling.policies.type = Policies

src/main/antlr4/edu/caltech/nanodb/sqlparse/NanoSQL.g4

@@ -358,8 +358,8 @@ expression:
       | expression op=( '<' | '<=' | '>' | '>=' | '=' | '==' | '!=' | '<>' ) expression     # ExprCompare
       | expression IS NOT? NULL                             # ExprIsNull
       | expression NOT? BETWEEN expression AND expression   # ExprBetween
-      | expression LIKE expression                          # ExprLike
-      | expression SIMILAR TO expression                    # ExprSimilarTo
+      | expression NOT? LIKE expression                     # ExprLike
+      | expression NOT? SIMILAR TO expression               # ExprSimilarTo
       | expression NOT? IN expressionList                   # ExprOneColInValues
       | expression NOT? IN '(' selectStmt ')'               # ExprOneColInSubquery
       | expressionList NOT? IN '(' selectStmt ')'           # ExprMultiColInSubquery

src/main/java/edu/caltech/nanodb/expressions/StringMatchOperator.java

@@ -74,6 +74,13 @@ public class StringMatchOperator extends Expression {
     Expression rightExpr;
 
 
+    /**
+     * If this is false, the operator computes <tt>IS LIKE</tt>; if true,
+     * the operator computes <tt>IS NOT LIKE</tt>.
+     */
+    private boolean invert;
+
+
     public StringMatchOperator(Type type, Expression lhs, Expression rhs) {
         if (type == null || lhs == null || rhs == null)
             throw new NullPointerException();
@@ -84,6 +91,11 @@ public class StringMatchOperator extends Expression {
     }
 
 
+    public void setInvert(boolean invert) {
+        this.invert = invert;
+    }
+
+
     public ColumnInfo getColumnInfo(Schema schema) throws SchemaNameException {
         // Comparisons always return Boolean values, so just pass a Boolean
         // value in to the TypeConverter to get out the corresponding SQL type.
@@ -189,7 +201,10 @@ public class StringMatchOperator extends Expression {
                     "Unrecognized string-matching type " + type);
         }
 
-        return Boolean.valueOf(result);
+        if (invert)
+            result = !result;
+
+        return result;
     }
 
 
@@ -211,6 +226,8 @@ public class StringMatchOperator extends Expression {
         String leftStr = leftExpr.toString();
         String rightStr = rightExpr.toString();
         String opStr = " " + type.stringRep() + " ";
+        if (invert)
+            opStr = " NOT" + opStr;
 
         // For now, assume we don't need parentheses.
 
@@ -260,7 +277,7 @@ public class StringMatchOperator extends Expression {
         if (obj instanceof StringMatchOperator) {
             StringMatchOperator other = (StringMatchOperator) obj;
 
-            return (type == other.type &&
+            return (type == other.type && invert == other.invert &&
                 leftExpr.equals(other.leftExpr) &&
                 rightExpr.equals(other.rightExpr));
         }
@@ -277,6 +294,7 @@ public class StringMatchOperator extends Expression {
     public int hashCode() {
         int hash = 7;
         hash = 31 * hash + type.hashCode();
+        hash = 31 * hash + Boolean.hashCode(invert);
         hash = 31 * hash + leftExpr.hashCode();
         hash = 31 * hash + rightExpr.hashCode();
         return hash;