diff --git a/include/utils/String8.h b/include/utils/String8.h
index cef8eca..b36f128 100644
--- a/include/utils/String8.h
+++ b/include/utils/String8.h
@@ -18,122 +18,16 @@
 #define ANDROID_STRING8_H
 
 #include <utils/Errors.h>
+#include <utils/SharedBuffer.h>
+#include <utils/Unicode.h>
 
-// Need this for the char16_t type; String8.h should not
-// be depedent on the String16 class.
-#include <utils/String16.h>
-
-#include <stdint.h>
-#include <string.h>
-#include <sys/types.h>
-
-// ---------------------------------------------------------------------------
-
-extern "C" {
-
-typedef uint32_t char32_t;
-
-size_t strlen32(const char32_t *);
-size_t strnlen32(const char32_t *, size_t);
-
-/*
- * Returns the length of "src" when "src" is valid UTF-8 string.
- * Returns 0 if src is NULL, 0-length string or non UTF-8 string.
- * This function should be used to determine whether "src" is valid UTF-8
- * characters with valid unicode codepoints. "src" must be null-terminated.
- *
- * If you are going to use other GetUtf... functions defined in this header
- * with string which may not be valid UTF-8 with valid codepoint (form 0 to
- * 0x10FFFF), you should use this function before calling others, since the
- * other functions do not check whether the string is valid UTF-8 or not.
- *
- * If you do not care whether "src" is valid UTF-8 or not, you should use
- * strlen() as usual, which should be much faster.
- */
-size_t utf8_length(const char *src);
-
-/*
- * Returns the UTF-32 length of "src".
- */
-size_t utf32_length(const char *src, size_t src_len);
-
-/*
- * Returns the UTF-8 length of "src".
- */
-size_t utf8_length_from_utf16(const char16_t *src, size_t src_len);
-
-/*
- * Returns the UTF-8 length of "src".
- */
-size_t utf8_length_from_utf32(const char32_t *src, size_t src_len);
-
-/*
- * Returns the unicode value at "index".
- * Returns -1 when the index is invalid (equals to or more than "src_len").
- * If returned value is positive, it is able to be converted to char32_t, which
- * is unsigned. Then, if "next_index" is not NULL, the next index to be used is
- * stored in "next_index". "next_index" can be NULL.
- */
-int32_t utf32_at(const char *src, size_t src_len,
-                 size_t index, size_t *next_index);
-
-/*
- * Stores a UTF-32 string converted from "src" in "dst", if "dst_length" is not
- * large enough to store the string, the part of the "src" string is stored
- * into "dst".
- * Returns the size actually used for storing the string.
- * "dst" is not null-terminated when dst_len is fully used (like strncpy).
- */
-size_t utf8_to_utf32(const char* src, size_t src_len,
-                     char32_t* dst, size_t dst_len);
-
-/*
- * Stores a UTF-8 string converted from "src" in "dst", if "dst_length" is not
- * large enough to store the string, the part of the "src" string is stored
- * into "dst" as much as possible. See the examples for more detail.
- * Returns the size actually used for storing the string.
- * dst" is not null-terminated when dst_len is fully used (like strncpy).
- *
- * Example 1
- * "src" == \u3042\u3044 (\xE3\x81\x82\xE3\x81\x84)
- * "src_len" == 2
- * "dst_len" >= 7
- * ->
- * Returned value == 6
- * "dst" becomes \xE3\x81\x82\xE3\x81\x84\0
- * (note that "dst" is null-terminated)
- *
- * Example 2
- * "src" == \u3042\u3044 (\xE3\x81\x82\xE3\x81\x84)
- * "src_len" == 2
- * "dst_len" == 5
- * ->
- * Returned value == 3
- * "dst" becomes \xE3\x81\x82\0
- * (note that "dst" is null-terminated, but \u3044 is not stored in "dst"
- * since "dst" does not have enough size to store the character)
- *
- * Example 3
- * "src" == \u3042\u3044 (\xE3\x81\x82\xE3\x81\x84)
- * "src_len" == 2
- * "dst_len" == 6
- * ->
- * Returned value == 6
- * "dst" becomes \xE3\x81\x82\xE3\x81\x84
- * (note that "dst" is NOT null-terminated, like strncpy)
- */
-size_t utf32_to_utf8(const char32_t* src, size_t src_len,
-                     char* dst, size_t dst_len);
-
-size_t utf16_to_utf8(const char16_t* src, size_t src_len,
-                     char* dst, size_t dst_len);
-
-}
+#include <string.h> // for strcmp
 
 // ---------------------------------------------------------------------------
 
 namespace android {
 
+class String16;
 class TextOutput;
 
 //! This is a string holding UTF-8 characters. Does not allow the value more
@@ -182,7 +76,7 @@
             size_t              getUtf32Length() const;
             int32_t             getUtf32At(size_t index,
                                            size_t *next_index) const;
-            size_t              getUtf32(char32_t* dst, size_t dst_len) const;
+            void                getUtf32(char32_t* dst) const;
 
     inline  String8&            operator=(const String8& other);
     inline  String8&            operator=(const char* other);