diff --git a/libs/binder/tests/binderClearBufTest.cpp b/libs/binder/tests/binderClearBufTest.cpp
index 2d30c8d..307151c 100644
--- a/libs/binder/tests/binderClearBufTest.cpp
+++ b/libs/binder/tests/binderClearBufTest.cpp
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#include <android-base/hex.h>
 #include <android-base/logging.h>
 #include <binder/Binder.h>
 #include <binder/IBinder.h>
@@ -30,22 +31,6 @@
 
 const String16 kServerName = String16("binderClearBuf");
 
-std::string hexString(const void* bytes, size_t len) {
-    if (bytes == nullptr) return "<null>";
-
-    const uint8_t* bytes8 = static_cast<const uint8_t*>(bytes);
-    char chars[] = "0123456789abcdef";
-    std::string result;
-    result.resize(len * 2);
-
-    for (size_t i = 0; i < len; i++) {
-        result[2 * i] = chars[bytes8[i] >> 4];
-        result[2 * i + 1] = chars[bytes8[i] & 0xf];
-    }
-
-    return result;
-}
-
 class FooBar : public BBinder {
  public:
     enum {
@@ -83,7 +68,7 @@
             lastReply = reply.data();
             lastReplySize = reply.dataSize();
         }
-        *outBuffer = hexString(lastReply, lastReplySize);
+        *outBuffer = android::base::HexString(lastReply, lastReplySize);
         return result;
     }
 };
diff --git a/libs/binder/tests/parcel_fuzzer/Android.bp b/libs/binder/tests/parcel_fuzzer/Android.bp
index 74b8eb8..acf3f8f 100644
--- a/libs/binder/tests/parcel_fuzzer/Android.bp
+++ b/libs/binder/tests/parcel_fuzzer/Android.bp
@@ -23,7 +23,6 @@
         "main.cpp",
         "random_fd.cpp",
         "random_parcel.cpp",
-        "util.cpp",
     ],
     static_libs: [
         "libbase",
diff --git a/libs/binder/tests/parcel_fuzzer/binder.cpp b/libs/binder/tests/parcel_fuzzer/binder.cpp
index a717ce9..f1fe164 100644
--- a/libs/binder/tests/parcel_fuzzer/binder.cpp
+++ b/libs/binder/tests/parcel_fuzzer/binder.cpp
@@ -18,11 +18,13 @@
 #include "binder.h"
 #include "util.h"
 
+#include <android-base/hex.h>
 #include <android/os/IServiceManager.h>
 #include <binder/ParcelableHolder.h>
 #include <binder/PersistableBundle.h>
 
 using ::android::status_t;
+using ::android::base::HexString;
 
 enum ByteEnum : int8_t {};
 enum IntEnum : int32_t {};
@@ -128,7 +130,7 @@
     [] (const ::android::Parcel& p, uint8_t len) {
         FUZZ_LOG() << "about to readInplace";
         const void* r = p.readInplace(len);
-        FUZZ_LOG() << "readInplace done. pointer: " << r << " bytes: " << hexString(r, len);
+        FUZZ_LOG() << "readInplace done. pointer: " << r << " bytes: " << (r ? HexString(r, len) : "null");
     },
     PARCEL_READ_OPT_STATUS(int32_t, readInt32),
     PARCEL_READ_OPT_STATUS(uint32_t, readUint32),
@@ -153,7 +155,7 @@
         FUZZ_LOG() << "about to readString8Inplace";
         size_t outLen = 0;
         const char* str = p.readString8Inplace(&outLen);
-        std::string bytes = hexString(str, sizeof(char) * (outLen + 1));
+        std::string bytes = str ? HexString(str, sizeof(char) * (outLen + 1)) : "null";
         FUZZ_LOG() << "readString8Inplace: " << bytes << " size: " << outLen;
     },
     PARCEL_READ_OPT_STATUS(android::String16, readString16),
@@ -163,7 +165,7 @@
         FUZZ_LOG() << "about to readString16Inplace";
         size_t outLen = 0;
         const char16_t* str = p.readString16Inplace(&outLen);
-        std::string bytes = hexString(str, sizeof(char16_t) * (outLen + 1));
+        std::string bytes = str ? HexString(str, sizeof(char16_t) * (outLen + 1)) : "null";
         FUZZ_LOG() << "readString16Inplace: " << bytes << " size: " << outLen;
     },
     PARCEL_READ_WITH_STATUS(android::sp<android::IBinder>, readStrongBinder),
diff --git a/libs/binder/tests/parcel_fuzzer/hwbinder.cpp b/libs/binder/tests/parcel_fuzzer/hwbinder.cpp
index 35b5ebc..ee9840f 100644
--- a/libs/binder/tests/parcel_fuzzer/hwbinder.cpp
+++ b/libs/binder/tests/parcel_fuzzer/hwbinder.cpp
@@ -18,10 +18,12 @@
 #include "hwbinder.h"
 #include "util.h"
 
+#include <android-base/hex.h>
 #include <android-base/logging.h>
 #include <hwbinder/Parcel.h>
 
 using ::android::status_t;
+using ::android::base::HexString;
 
 // TODO: support scatter-gather types
 
@@ -70,13 +72,13 @@
         FUZZ_LOG() << "about to read";
         std::vector<uint8_t> data (length);
         status_t status = p.read(data.data(), length);
-        FUZZ_LOG() << "read status: " << status << " data: " << hexString(data.data(), data.size());
+        FUZZ_LOG() << "read status: " << status << " data: " << HexString(data.data(), data.size());
     },
     [] (const ::android::hardware::Parcel& p, uint8_t length) {
         FUZZ_LOG() << "about to read";
         std::vector<uint8_t> data (length);
         const void* inplace = p.readInplace(length);
-        FUZZ_LOG() << "read status: " << hexString(inplace, length);
+        FUZZ_LOG() << "read status: " << (inplace ? HexString(inplace, length) : "null");
     },
     PARCEL_READ_WITH_STATUS(int8_t, readInt8),
     PARCEL_READ_WITH_STATUS(uint8_t, readUint8),
@@ -100,7 +102,7 @@
         FUZZ_LOG() << "about to readString16Inplace";
         size_t outSize = 0;
         const char16_t* str = p.readString16Inplace(&outSize);
-        FUZZ_LOG() << "readString16Inplace: " << hexString(str, sizeof(char16_t) * outSize);
+        FUZZ_LOG() << "readString16Inplace: " << HexString(str, sizeof(char16_t) * outSize);
     },
     PARCEL_READ_OPT_STATUS(::android::sp<::android::hardware::IBinder>, readStrongBinder),
     PARCEL_READ_WITH_STATUS(::android::sp<::android::hardware::IBinder>, readNullableStrongBinder),
diff --git a/libs/binder/tests/parcel_fuzzer/main.cpp b/libs/binder/tests/parcel_fuzzer/main.cpp
index 2a79e85..f435dae 100644
--- a/libs/binder/tests/parcel_fuzzer/main.cpp
+++ b/libs/binder/tests/parcel_fuzzer/main.cpp
@@ -22,6 +22,7 @@
 
 #include <iostream>
 
+#include <android-base/hex.h>
 #include <android-base/logging.h>
 #include <android/binder_auto_utils.h>
 #include <android/binder_libbinder.h>
@@ -35,6 +36,7 @@
 
 using android::fillRandomParcel;
 using android::sp;
+using android::base::HexString;
 
 void fillRandomParcel(::android::hardware::Parcel* p, FuzzedDataProvider&& provider) {
     // TODO: functionality to create random parcels for libhwbinder parcels
@@ -78,8 +80,8 @@
     CHECK(reads.size() <= 255) << reads.size();
 
     FUZZ_LOG() << "backend: " << backend;
-    FUZZ_LOG() << "input: " << hexString(p.data(), p.dataSize());
-    FUZZ_LOG() << "instructions: " << hexString(instructions);
+    FUZZ_LOG() << "input: " << HexString(p.data(), p.dataSize());
+    FUZZ_LOG() << "instructions: " << HexString(instructions.data(), instructions.size());
 
     for (size_t i = 0; i + 1 < instructions.size(); i += 2) {
         uint8_t a = instructions[i];
diff --git a/libs/binder/tests/parcel_fuzzer/util.cpp b/libs/binder/tests/parcel_fuzzer/util.cpp
deleted file mode 100644
index 479f406..0000000
--- a/libs/binder/tests/parcel_fuzzer/util.cpp
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Copyright (C) 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#define FUZZ_LOG_TAG "util"
-#include "util.h"
-
-#include <android-base/logging.h>
-
-#include <iomanip>
-#include <sstream>
-
-std::string hexString(const void* bytes, size_t len) {
-    if (bytes == nullptr) return "<null>";
-
-    const uint8_t* bytes8 = static_cast<const uint8_t*>(bytes);
-    char chars[] = "0123456789abcdef";
-    std::string result;
-    result.resize(len * 2);
-
-    for (size_t i = 0; i < len; i++) {
-        result[2 * i] = chars[bytes8[i] >> 4];
-        result[2 * i + 1] = chars[bytes8[i] & 0xf];
-    }
-
-    return result;
-}
-std::string hexString(const std::vector<uint8_t>& bytes) {
-    return hexString(bytes.data(), bytes.size());
-}
diff --git a/libs/binder/tests/parcel_fuzzer/util.h b/libs/binder/tests/parcel_fuzzer/util.h
index 45e8c57..a5d0dae 100644
--- a/libs/binder/tests/parcel_fuzzer/util.h
+++ b/libs/binder/tests/parcel_fuzzer/util.h
@@ -49,6 +49,3 @@
     FuzzLog& log() { return *this; }
 };
 #endif
-
-std::string hexString(const void* bytes, size_t len);
-std::string hexString(const std::vector<uint8_t>& bytes);