From 591efdc554efe55cb0ab7f88e6d4c45b247987c3 Mon Sep 17 00:00:00 2001
From: Freddy Mallet <freddy.mallet@gmail.com>
Date: Sat, 23 Apr 2011 00:47:42 +0200
Subject: [PATCH] SONAR-2384 First implementation : Create a markdown dedicated
 to Sonar needs

---
 .../java/org/sonar/channel/RegexChannel.java  | 42 ++++++++++++++
 .../org/sonar/channel/RegexChannelTest.java   | 58 +++++++++++++++++++
 2 files changed, 100 insertions(+)
 create mode 100644 sonar-channel/src/main/java/org/sonar/channel/RegexChannel.java
 create mode 100644 sonar-channel/src/test/java/org/sonar/channel/RegexChannelTest.java

diff --git a/sonar-channel/src/main/java/org/sonar/channel/RegexChannel.java b/sonar-channel/src/main/java/org/sonar/channel/RegexChannel.java
new file mode 100644
index 00000000000..5b2a744a227
--- /dev/null
+++ b/sonar-channel/src/main/java/org/sonar/channel/RegexChannel.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2010 SonarSource SA
+ * All rights reserved
+ * mailto:contact AT sonarsource DOT com
+ */
+package org.sonar.channel;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public abstract class RegexChannel<OUTPUT> extends Channel<OUTPUT> {
+
+  private final StringBuilder tmpBuilder = new StringBuilder();
+  private final Matcher matcher;
+  private final String regex;
+
+  public RegexChannel(String regex) {
+    matcher = Pattern.compile(regex).matcher("");
+    this.regex = regex;
+  }
+
+  @Override
+  public final boolean consume(CodeReader code, OUTPUT output) {
+    try {
+      if (code.popTo(matcher, tmpBuilder) > 0) {
+        consume(tmpBuilder, output);
+        tmpBuilder.delete(0, tmpBuilder.length());
+        return true;
+      }
+      return false;
+    } catch (StackOverflowError e) {
+      throw new RuntimeException(
+          "The regular expression "
+              + regex
+              + " has led to a stack overflow error. "
+              + "This error is certainly due to an inefficient use of alternations. See http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5050507",
+          e);
+    }
+  }
+
+  protected abstract void consume(CharSequence token, OUTPUT output);
+}
diff --git a/sonar-channel/src/test/java/org/sonar/channel/RegexChannelTest.java b/sonar-channel/src/test/java/org/sonar/channel/RegexChannelTest.java
new file mode 100644
index 00000000000..7fb5c3a11ab
--- /dev/null
+++ b/sonar-channel/src/test/java/org/sonar/channel/RegexChannelTest.java
@@ -0,0 +1,58 @@
+/*
+ * Sonar, open source software quality management tool.
+ * Copyright (C) 2008-2011 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * Sonar is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * Sonar is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Sonar; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
+ */
+package org.sonar.channel;
+
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+import org.junit.Test;
+
+public class RegexChannelTest {
+
+  @Test
+  public void shouldMatch() {
+    ChannelDispatcher<StringBuilder> dispatcher = new ChannelDispatcher<StringBuilder>(new MyWordChannel(), new BlackholeChannel());
+    StringBuilder output = new StringBuilder();
+    dispatcher.consume(new CodeReader("my word"), output);
+    assertThat(output.toString(), is("<w>my</w> <w>word</w>"));
+  }
+
+  private class MyWordChannel extends RegexChannel<StringBuilder> {
+
+    public MyWordChannel() {
+      super("\\w++");
+    }
+
+    @Override
+    protected void consume(CharSequence token, StringBuilder output) {
+      output.append("<w>" + token + "</w>");
+    }
+  }
+
+  class BlackholeChannel extends Channel<StringBuilder> {
+
+    @Override
+    public boolean consume(CodeReader code, StringBuilder output) {
+      output.append((char) code.pop());
+      return true;
+    }
+  }
+
+}
-- 
2.39.5