H2 Console: improved autocomplete feature (also simplified the source code for this feature).

h2/src/main/org/h2/bnf/Bnf.java

@@ -280,7 +280,9 @@ public class Bnf {
                 continue;
             }
             sentence.start();
-            head.getRule().addNextTokenList(sentence);
+            if (head.getRule().autoComplete(sentence)) {
+                break;
+            }
         }
         return sentence.getNext();
     }

h2/src/main/org/h2/bnf/Rule.java

@@ -28,23 +28,13 @@ public interface Rule {
     void setLinks(HashMap<String, RuleHead> ruleMap);
 
     /**
-     * Add the next possible token for a query.
-     * Used for autocomplete support.
+     * Add the next possible token(s). If there was a match, the query in the
+     * sentence is updated (the matched token is removed).
      *
      * @param sentence the sentence context
+     * @return true if a full match
      */
-    void addNextTokenList(Sentence sentence);
-
-    /**
-     * Remove a token from a sentence. Used for autocomplete support.
-     * If there was a match, the query in the sentence is updated
-     * (the matched token is removed).
-     *
-     * @param sentence
-     *            the sentence context
-     * @return false if not a match or a partial match, true if a full match
-     */
-    boolean matchRemove(Sentence sentence);
+    boolean autoComplete(Sentence sentence);
 
     /**
      * Call the visit method in the given visitor.

h2/src/main/org/h2/bnf/RuleElement.java

@@ -29,10 +29,6 @@ public class RuleElement implements Rule {
         this.type = topic.startsWith("function") ? Sentence.FUNCTION : Sentence.KEYWORD;
     }
 
-    public String toString() {
-        return name;
-    }
-
     public void accept(BnfVisitor visitor) {
         visitor.visitRuleElement(keyword, name, link);
     }
@@ -60,16 +56,14 @@ public class RuleElement implements Rule {
         throw new AssertionError("Unknown " + name + "/" + test);
     }
 
-    public boolean matchRemove(Sentence sentence) {
+    public boolean autoComplete(Sentence sentence) {
         if (sentence.shouldStop()) {
             return false;
         }
-        String query = sentence.getQuery();
-        if (query.length() == 0) {
-            return false;
-        }
         if (keyword) {
-            String up = sentence.getQueryUpper();
+            String query = sentence.getQuery();
+            String q = query.trim();
+            String up = sentence.getQueryUpper().trim();
             if (up.startsWith(name)) {
                 query = query.substring(name.length());
                 while (!"_".equals(name) && query.length() > 0 && Character.isWhitespace(query.charAt(0))) {
@@ -77,38 +71,18 @@ public class RuleElement implements Rule {
                 }
                 sentence.setQuery(query);
                 return true;
+            } else if (q.length() == 0 || name.startsWith(up)) {
+                if (q.length() < name.length()) {
+                    sentence.add(name, name.substring(q.length()), type);
                 }
-            return false;
             }
-        if (!link.matchRemove(sentence)) {
             return false;
         }
-        if (name != null && !name.startsWith("@") && (link.name() == null || !link.name().startsWith("@"))) {
-            query = sentence.getQuery();
-            while (query.length() > 0 && Character.isWhitespace(query.charAt(0))) {
-                query = query.substring(1);
-            }
-            sentence.setQuery(query);
-        }
-        return true;
+        return link.autoComplete(sentence);
     }
 
-    public void addNextTokenList(Sentence sentence) {
-        if (sentence.shouldStop()) {
-            return;
-        }
-        if (keyword) {
-            String query = sentence.getQuery();
-            String q = query.trim();
-            String up = sentence.getQueryUpper().trim();
-            if (q.length() == 0 || name.startsWith(up)) {
-                if (q.length() < name.length()) {
-                    sentence.add(name, name.substring(q.length()), type);
-                }
-            }
-            return;
-        }
-        link.addNextTokenList(sentence);
+    public String toString() {
+        return name;
     }
 
 }

h2/src/main/org/h2/bnf/RuleList.java

@@ -9,7 +9,6 @@ package org.h2.bnf;
 import java.util.ArrayList;
 import java.util.HashMap;
 import org.h2.util.New;
-import org.h2.util.StatementBuilder;
 
 /**
  * Represents a sequence of BNF rules, or a list of alternative rules.
@@ -35,24 +34,6 @@ public class RuleList implements Rule {
         this.or = or;
     }
 
-    public String toString() {
-        StatementBuilder buff = new StatementBuilder();
-        if (or) {
-            buff.append('{');
-            for (Rule r : list) {
-                buff.appendExceptFirst("|");
-                buff.append(r.toString());
-            }
-            buff.append('}');
-        } else {
-            for (Rule r : list) {
-                buff.appendExceptFirst(" ");
-                buff.append(r.toString());
-            }
-        }
-        return buff.toString();
-    }
-
     public void accept(BnfVisitor visitor) {
         visitor.visitRuleList(or, list);
     }
@@ -70,43 +51,32 @@ public class RuleList implements Rule {
         }
     }
 
-    public boolean matchRemove(Sentence sentence) {
-        String query = sentence.getQuery();
-        if (query.length() == 0) {
+    public boolean autoComplete(Sentence sentence) {
+        if (sentence.shouldStop()) {
             return false;
         }
+        String old = sentence.getQuery();
         if (or) {
             for (Rule r : list) {
-                if (r.matchRemove(sentence)) {
+                sentence.setQuery(old);
+                if (r.autoComplete(sentence)) {
                     return true;
                 }
             }
             return false;
-        }
+        } else {
             for (Rule r : list) {
-            if (!r.matchRemove(sentence)) {
+                if (!r.autoComplete(sentence)) {
+                    sentence.setQuery(old);
                     return false;
                 }
             }
             return true;
         }
-
-    public void addNextTokenList(Sentence sentence) {
-        String old = sentence.getQuery();
-        if (or) {
-            for (Rule r : list) {
-                sentence.setQuery(old);
-                r.addNextTokenList(sentence);
-            }
-        } else {
-            for (Rule r : list) {
-                r.addNextTokenList(sentence);
-                if (!r.matchRemove(sentence)) {
-                    break;
-                }
-            }
     }
-        sentence.setQuery(old);
+
+    public String toString() {
+        return or ? "or: " : "" + list.toString();
     }
 
 }

h2/src/main/org/h2/bnf/RuleOptional.java

@@ -19,10 +19,6 @@ public class RuleOptional implements Rule {
         this.rule = rule;
     }
 
-    public String toString() {
-        return "[" + rule.toString() + "]";
-    }
-
     public void accept(BnfVisitor visitor) {
         visitor.visitRuleOptional(rule);
     }
@@ -37,26 +33,16 @@ public class RuleOptional implements Rule {
             mapSet = true;
         }
     }
-
-    public boolean matchRemove(Sentence sentence) {
+    public boolean autoComplete(Sentence sentence) {
         if (sentence.shouldStop()) {
             return false;
         }
-        String query = sentence.getQuery();
-        if (query.length() == 0) {
-            return true;
-        }
-        if (!rule.matchRemove(sentence)) {
-            return true;
-        }
+        rule.autoComplete(sentence);
         return true;
     }
 
-    public void addNextTokenList(Sentence sentence) {
-        if (sentence.shouldStop()) {
-            return;
-        }
-        rule.addNextTokenList(sentence);
+    public String toString() {
+        return rule.toString();
     }
 
 }

h2/src/main/org/h2/bnf/RuleRepeat.java

@@ -21,10 +21,6 @@ public class RuleRepeat implements Rule {
         this.comma = comma;
     }
 
-    public String toString() {
-        return "...";
-    }
-
     public void accept(BnfVisitor visitor) {
         visitor.visitRuleRepeat(comma, rule);
     }
@@ -37,36 +33,18 @@ public class RuleRepeat implements Rule {
         // rule.setLinks(ruleMap);
     }
 
-    public boolean matchRemove(Sentence sentence) {
+    public boolean autoComplete(Sentence sentence) {
         if (sentence.shouldStop()) {
             return false;
         }
-        String query = sentence.getQuery();
-        if (query.length() == 0) {
-            return false;
+        while (rule.autoComplete(sentence)) {
+            // nothing to do
         }
-        while (true) {
-            if (!rule.matchRemove(sentence)) {
         return true;
     }
-            if (sentence.getQuery().length() == 0) {
-                return true;
-            }
-        }
-    }
 
-    public void addNextTokenList(Sentence sentence) {
-        if (sentence.shouldStop()) {
-            return;
-        }
-        String old = sentence.getQuery();
-        while (true) {
-            rule.addNextTokenList(sentence);
-            if (!rule.matchRemove(sentence) || old.equals(sentence.getQuery())) {
-                break;
-            }
-        }
-        sentence.setQuery(old);
+    public String toString() {
+        return rule.toString();
     }
 
 }