refactor(core): StringEncoding (#300)

* refactor(core): StringEncoding

* chore(notice): remove JanusGraph

* chore(notice): remove all notice about JanusGraph

Author: diaohancai

.licenserc.yaml

@@ -72,7 +72,6 @@ header: # `header` section is configurations for source codes license header.
     - 'assembly/**'
     - '.github/**/*'
     - '**/target/*'
-    - '**/util/StringEncoding.java'
     - '**/go.mod'
     - '**/go.sum'
   comment: on-failure # on what condition license-eye will comment on the pull request, `on-failure`, `always`, `never`.

LICENSE

@@ -199,12 +199,3 @@
    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.
-   
-========================================================================
-Apache 2.0 licenses
-========================================================================
-
-The following components are provided under the Apache License. See project link for details.
-The text of each license is the standard Apache 2.0 license.
-
-computer-core/src/main/java/org/apache/hugegraph/computer/core/util/StringEncoding.java files from https://github.com/JanusGraph

NOTICE

@@ -5,56 +5,3 @@ This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
 
 The initial codebase was donated to the ASF by HugeGraph Authors, copyright 2017-2021.
-
------------------------------------------------------------------------
-This product contains code form the JanusGraph Project:
------------------------------------------------------------------------
-==============================================================
- JanusGraph: Distributed Graph Database
- Copyright 2012 and onwards JanusGraph Authors
-==============================================================
-
-This product includes software developed by JanusGraph contributors listed
-in CONTRIBUTORS.txt; JanusGraph copyright holders are listed in AUTHORS.txt.
-
-This product is based on Titan, originally developed by Aurelius (acquired by
-DataStax) and the following individuals:
-
- * Matthias Broecheler
- * Dan LaRocque
- * Marko A. Rodriguez
- * Stephen Mallette
- * Pavel Yaskevich
-
-It also includes software from other open source projects including, but not limited to (check pom.xml for complete listing):
-
- * Apache Cassandra [https://cassandra.apache.org/]
- * Apache Commons [https://commons.apache.org/]
- * Apache Groovy [http://groovy-lang.org/]
- * Apache HBase [https://hbase.apache.org/]
- * Apache Hadoop [https://hadoop.apache.org/]
- * Apache Kerby [https://github.com/apache/directory-kerby]
- * Apache Log4j [https://logging.apache.org/log4j]
- * Apache Lucene [https://lucene.apache.org/]
- * Apache Solr [https://lucene.apache.org/solr/]
- * Apache TinkerPop [https://tinkerpop.apache.org/]
- * Astyanax [https://github.com/Netflix/astyanax]
- * DataStax Driver for Apache Cassandra  [https://github.com/datastax/java-driver]
- * EasyMock [http://easymock.org/]
- * Elasticsearch [https://www.elastic.co/]
- * Google Cloud Bigtable [https://github.com/googlecloudplatform/cloud-bigtable-client]
- * Google Guava [https://github.com/google/guava]
- * HPPC [https://labs.carrotsearch.com/hppc.html]
- * JUnit [https://www.junit.org/]
- * Jackson [https://github.com/FasterXML/jackson]
- * Kryo [https://github.com/EsotericSoftware/kryo]
- * Metrics [https://metrics.dropwizard.io]
- * Mockito [https://site.mockito.org/]
- * Noggit [https://github.com/yonik/noggit]
- * OpenRDF [http://rdf4j.org/]
- * Oracle BerkeleyDB Java Edition [https://www.oracle.com/technetwork/products/berkeleydb/] (see license below)
- * Project Lombok [https://projectlombok.org/]
- * Reflections8 [https://github.com/aschoerk/reflections8]
- * SLF4J [https://www.slf4j.org/]
- * Spatial4j [https://github.com/locationtech/spatial4j]
- * Vavr [https://www.vavr.io/]

computer-core/src/main/java/org/apache/hugegraph/computer/core/io/StructRandomAccessOutput.java

@@ -20,7 +20,7 @@
 import java.io.IOException;
 
 import org.apache.commons.lang3.StringEscapeUtils;
-import org.apache.hugegraph.computer.core.util.StringEncoding;
+import org.apache.hugegraph.computer.core.util.StringEncodeUtil;
 import org.apache.hugegraph.testutil.Whitebox;
 
 @SuppressWarnings("deprecation") // StringEscapeUtils
@@ -67,14 +67,14 @@ public void write(int b) throws IOException {
 
     @Override
     public void write(byte[] b) throws IOException {
-        this.writeString(StringEncoding.encodeBase64(b));
+        this.writeString(StringEncodeUtil.encodeBase64(b));
     }
 
     @Override
     public void write(byte[] b, int off, int len) throws IOException {
         byte[] dest = new byte[len];
         System.arraycopy(b, off, dest, 0, len);
-        this.writeString(StringEncoding.encodeBase64(dest));
+        this.writeString(StringEncodeUtil.encodeBase64(dest));
     }
 
     @Override

computer-core/src/main/java/org/apache/hugegraph/computer/core/network/TransportUtil.java

@@ -27,7 +27,7 @@
 import java.util.List;
 
 import org.apache.hugegraph.computer.core.common.exception.ComputerException;
-import org.apache.hugegraph.computer.core.util.StringEncoding;
+import org.apache.hugegraph.computer.core.util.StringEncodeUtil;
 import org.apache.hugegraph.util.E;
 import org.apache.hugegraph.util.Log;
 import org.slf4j.Logger;
@@ -146,12 +146,12 @@ public static String readString(ByteBuf buf) {
         }
         byte[] bytes = new byte[length];
         buf.readBytes(bytes);
-        return StringEncoding.decode(bytes);
+        return StringEncodeUtil.decode(bytes);
     }
 
     public static void writeString(ByteBuf buf, String value) {
         E.checkArgumentNotNull(value, "value");
-        byte[] encoded = StringEncoding.encode(value);
+        byte[] encoded = StringEncodeUtil.encode(value);
         buf.writeInt(encoded.length);
         buf.writeBytes(encoded);
     }

computer-core/src/main/java/org/apache/hugegraph/computer/core/output/hdfs/HdfsOutput.java

@@ -31,7 +31,7 @@
 import org.apache.hugegraph.computer.core.config.Config;
 import org.apache.hugegraph.computer.core.graph.vertex.Vertex;
 import org.apache.hugegraph.computer.core.output.AbstractComputerOutput;
-import org.apache.hugegraph.computer.core.util.StringEncoding;
+import org.apache.hugegraph.computer.core.util.StringEncodeUtil;
 import org.apache.hugegraph.util.Log;
 import org.slf4j.Logger;
 
@@ -93,7 +93,7 @@ protected void writeBytes(byte[] bytes) throws IOException {
     }
 
     protected void writeString(String string) throws IOException {
-        this.writeBytes(StringEncoding.encode(string));
+        this.writeBytes(StringEncodeUtil.encode(string));
     }
 
     protected String constructValueString(Vertex vertex) {

computer-core/src/main/java/org/apache/hugegraph/computer/core/util/StringEncodeUtil.java

@@ -0,0 +1,52 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with this
+ * work for additional information regarding copyright ownership. The ASF
+ * licenses this file to You 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.
+ */
+
+package org.apache.hugegraph.computer.core.util;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+
+public final class StringEncodeUtil {
+
+    private static final byte[] BYTES_EMPTY = new byte[0];
+
+    private static final Base64.Encoder BASE64_ENCODER = Base64.getEncoder();
+    private static final Base64.Decoder BASE64_DECODER = Base64.getDecoder();
+
+    public static byte[] encode(String value) {
+        return value.getBytes(StandardCharsets.UTF_8);
+    }
+
+    public static String decode(byte[] bytes) {
+        return new String(bytes, StandardCharsets.UTF_8);
+    }
+
+    public static String decode(byte[] bytes, int offset, int length) {
+        return new String(bytes, offset, length, StandardCharsets.UTF_8);
+    }
+
+    public static String encodeBase64(byte[] bytes) {
+        return BASE64_ENCODER.encodeToString(bytes);
+    }
+
+    public static byte[] decodeBase64(String value) {
+        if (value.isEmpty()) {
+            return BYTES_EMPTY;
+        }
+        return BASE64_DECODER.decode(value);
+    }
+}

computer-core/src/main/java/org/apache/hugegraph/computer/core/util/StringEncoding.java

@@ -400,8 +400,6 @@ The following components are provided under the Apache 2.0 License.
     (Apache License, Version 2.0) * okio(com.squareup.okio:okio-jvm:3.0.0-https://github.com/square/okio/ )
     (Apache License, Version 2.0) * Simple XML (safe)(com.carrotsearch.thirdparty:simple-xml-safe:2.7.1-https://github.com/dweiss/simplexml )
 
-    computer-core/src/main/java/org/apache/hugegraph/computer/core/util/StringEncoding.java files from https://github.com/JanusGraph
-
 ========================================================================
 Third party BSD licenses
 ========================================================================