Helper classes for java bindings.

Review URL: https://codereview.chromium.org/288133005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@270757 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 133 insertions, 0 deletions

diff --git a/mojo/android/javatests/src/org/chromium/mojo/bindings/BindingsHelperTest.java b/mojo/android/javatests/src/org/chromium/mojo/bindings/BindingsHelperTest.java
new file mode 100644
index 0000000..a46a157
--- /dev/null
+++ b/mojo/android/javatests/src/org/chromium/mojo/bindings/BindingsHelperTest.java
@@ -0,0 +1,55 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.mojo.bindings;
+
+import android.test.suitebuilder.annotation.SmallTest;
+
+import junit.framework.TestCase;
+
+import java.nio.charset.Charset;
+
+/**
+ * Testing {@link BindingsHelper}.
+ */
+public class BindingsHelperTest extends TestCase {
+
+    /**
+     * Testing {@link BindingsHelper#utf8StringSizeInBytes(String)}.
+     */
+    @SmallTest
+    public void testUTF8StringLength() {
+        String[] stringsToTest = {
+            "",
+            "a",
+            "hello world",
+            "éléphant",
+            "𠜎𠜱𠝹𠱓𠱸𠲖𠳏𠳕",
+            "你午饭想吃什么",
+            "你午饭想吃什么\0éléphant",
+        };
+        for (String s : stringsToTest) {
+            assertEquals(s.getBytes(Charset.forName("utf8")).length,
+                    BindingsHelper.utf8StringSizeInBytes(s));
+        }
+        assertEquals(1, BindingsHelper.utf8StringSizeInBytes("\0"));
+        String s = new StringBuilder().appendCodePoint(0x0).appendCodePoint(0x80).
+                appendCodePoint(0x800).appendCodePoint(0x10000).toString();
+        assertEquals(10, BindingsHelper.utf8StringSizeInBytes(s));
+        assertEquals(10, s.getBytes(Charset.forName("utf8")).length);
+    }
+
+    /**
+     * Testing {@link BindingsHelper#align(int)}.
+     */
+    @SmallTest
+    public void testAlign() {
+        for (int i = 0; i < 3 * BindingsHelper.ALIGNMENT; ++i) {
+            int j = BindingsHelper.align(i);
+            assertTrue(j >= i);
+            assertTrue(j % BindingsHelper.ALIGNMENT == 0);
+            assertTrue(j - i < BindingsHelper.ALIGNMENT);
+        }
+    }
+}
diff --git a/mojo/bindings/java/src/org/chromium/mojo/bindings/BindingsHelper.java b/mojo/bindings/java/src/org/chromium/mojo/bindings/BindingsHelper.java
new file mode 100644
index 0000000..f2aa046
--- /dev/null
+++ b/mojo/bindings/java/src/org/chromium/mojo/bindings/BindingsHelper.java
@@ -0,0 +1,64 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.mojo.bindings;
+
+/**
+ * Helper functions.
+ */
+public class BindingsHelper {
+    /**
+     * Alignment in byte for mojo serialization.
+     */
+    public static final int ALIGNMENT = 8;
+
+    /**
+     * Align |size| on {@link BindingsHelper#ALIGNMENT}.
+     */
+    public static int align(int size) {
+        return (size + ALIGNMENT - 1) & ~(ALIGNMENT - 1);
+    }
+
+    /**
+     * Compute the size in bytes of the given string encoded as utf8.
+     */
+    public static int utf8StringSizeInBytes(String s) {
+        int res = 0;
+        for (int i = 0; i < s.length(); ++i) {
+            char c = s.charAt(i);
+            int codepoint = c;
+            if (isSurrogate(c)) {
+                i++;
+                char c2 = s.charAt(i);
+                codepoint = Character.toCodePoint(c, c2);
+            }
+            res += 1;
+            if (codepoint > 0x7f) {
+                res += 1;
+                if (codepoint > 0x7ff) {
+                    res += 1;
+                    if (codepoint > 0xffff) {
+                        res += 1;
+                        if (codepoint > 0x1fffff) {
+                            res += 1;
+                            if (codepoint > 0x3ffffff) {
+                                res += 1;
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        return res;
+    }
+
+    /**
+     * Determines if the given {@code char} value is a Unicode <i>surrogate code unit</i>. See
+     * {@link Character#isSurrogate}. Extracting here because the method only exists at API level
+     * 19.
+     */
+    private static boolean isSurrogate(char c) {
+        return c >= Character.MIN_SURROGATE && c < (Character.MAX_SURROGATE + 1);
+    }
+}
diff --git a/mojo/mojo.gyp b/mojo/mojo.gyp
index f86252f..9d0b02c 100644
--- a/mojo/mojo.gyp
+++ b/mojo/mojo.gyp
@@ -69,6 +69,7 @@
         }],
         ['OS == "android"', {
           'dependencies': [
+            'mojo_bindings_java',
             'mojo_public_java',
             'mojo_system_java',
             'libmojo_system_java',
@@ -737,6 +738,8 @@
           'target_name': 'mojo_test_apk',
           'type': 'none',
           'dependencies': [
+            'mojo_bindings_java',
+            'mojo_public_test_interfaces',
             'mojo_system_java',
             '../base/base.gyp:base_java_test_support',
           ],
diff --git a/mojo/mojo_public.gypi b/mojo/mojo_public.gypi
index 65102eb..9dac104 100644
--- a/mojo/mojo_public.gypi
+++ b/mojo/mojo_public.gypi
@@ -387,6 +387,17 @@
           },
           'includes': [ '../build/java.gypi' ],
         },
+        {
+          'target_name': 'mojo_bindings_java',
+          'type': 'none',
+          'variables': {
+            'java_in_dir': 'bindings/java',
+          },
+          'dependencies': [
+            'mojo_public_java',
+          ],
+          'includes': [ '../build/java.gypi' ],
+        },
       ],
     }],
   ],