fix boot 2 upgrade, rename package

spring-rest-query-language/src/main/java/com/baeldung/web/util/CriteriaParser.java

@@ -0,0 +1,77 @@
+package com.baeldung.web.util;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Deque;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import com.google.common.base.Joiner;
+
+public class CriteriaParser {
+
+    private static Map<String, Operator> ops;
+
+    private static Pattern SpecCriteraRegex = Pattern.compile("^(\\w+?)(" + Joiner.on("|")
+        .join(SearchOperation.SIMPLE_OPERATION_SET) + ")(\\p{Punct}?)(\\w+?)(\\p{Punct}?)$");
+
+    private enum Operator {
+        OR(1), AND(2);
+        final int precedence;
+
+        Operator(int p) {
+            precedence = p;
+        }
+    }
+
+    static {
+        Map<String, Operator> tempMap = new HashMap<>();
+        tempMap.put("AND", Operator.AND);
+        tempMap.put("OR", Operator.OR);
+        tempMap.put("or", Operator.OR);
+        tempMap.put("and", Operator.AND);
+
+        ops = Collections.unmodifiableMap(tempMap);
+    }
+
+    private static boolean isHigerPrecedenceOperator(String currOp, String prevOp) {
+        return (ops.containsKey(prevOp) && ops.get(prevOp).precedence >= ops.get(currOp).precedence);
+    }
+
+    public Deque<?> parse(String searchParam) {
+
+        Deque<Object> output = new LinkedList<>();
+        Deque<String> stack = new LinkedList<>();
+
+        Arrays.stream(searchParam.split("\\s+")).forEach(token -> {
+            if (ops.containsKey(token)) {
+                while (!stack.isEmpty() && isHigerPrecedenceOperator(token, stack.peek()))
+                    output.push(stack.pop()
+                        .equalsIgnoreCase(SearchOperation.OR_OPERATOR) ? SearchOperation.OR_OPERATOR : SearchOperation.AND_OPERATOR);
+                stack.push(token.equalsIgnoreCase(SearchOperation.OR_OPERATOR) ? SearchOperation.OR_OPERATOR : SearchOperation.AND_OPERATOR);
+            } else if (token.equals(SearchOperation.LEFT_PARANTHESIS)) {
+                stack.push(SearchOperation.LEFT_PARANTHESIS);
+            } else if (token.equals(SearchOperation.RIGHT_PARANTHESIS)) {
+                while (!stack.peek()
+                    .equals(SearchOperation.LEFT_PARANTHESIS))
+                    output.push(stack.pop());
+                stack.pop();
+            } else {
+
+                Matcher matcher = SpecCriteraRegex.matcher(token);
+                while (matcher.find()) {
+                    output.push(new SpecSearchCriteria(matcher.group(1), matcher.group(2), matcher.group(3), matcher.group(4), matcher.group(5)));
+                }
+            }
+        });
+
+        while (!stack.isEmpty())
+            output.push(stack.pop());
+
+        return output;
+    }
+
+}