refactor: refactor some code

ingester-common/src/main/java/com/google/protobuf/ByteStringHelper.java

@@ -15,9 +15,6 @@
  */
 package com.google.protobuf;
 
-import java.io.IOException;
-import java.nio.ByteBuffer;
-
 /**
  * A {@code ByteString} helper, avoid some memory copying to improve performance.
  *
@@ -31,43 +28,4 @@ public class ByteStringHelper {
     public static ByteString wrap(byte[] bs) {
         return ByteString.wrap(bs);
     }
-
-    /**
-     * Wrap a byte array into a ByteString.
-     *
-     * @param bs the byte array
-     * @param offset read start offset in array
-     * @param len read data length
-     * @return the result byte string.
-     */
-    public static ByteString wrap(byte[] bs, int offset, int len) {
-        return ByteString.wrap(bs, offset, len);
-    }
-
-    /**
-     * Wrap a byte buffer into a ByteString.
-     */
-    public static ByteString wrap(ByteBuffer buf) {
-        return ByteString.wrap(buf);
-    }
-
-    /**
-     * Steal the byte[] from {@link ByteString}, if failed,
-     * then call {@link ByteString#toByteArray()}.
-     *
-     * @param byteString the byteString source data
-     * @return carried bytes
-     */
-    public static byte[] sealByteArray(ByteString byteString) {
-        BytesStealer stealer = new BytesStealer();
-        try {
-            byteString.writeTo(stealer);
-            if (stealer.isValid()) {
-                return stealer.value();
-            }
-        } catch (IOException ignored) {
-            // ignored
-        }
-        return byteString.toByteArray();
-    }
 }

ingester-common/src/main/java/io/greptime/common/signal/SignalHelper.java

@@ -104,7 +104,7 @@ public void handle(sun.misc.Signal signal) {
                     h.handle(signal.getName());
                 }
             } catch (Throwable t) {
-                LOG.error("Fail to handle signal: {}.", signal, t);
+                LOG.error("Failed to handle signal: {}.", signal, t);
             }
         }
     }

ingester-common/src/main/java/io/greptime/common/util/StringBuilderHelper.java

@@ -22,14 +22,13 @@
  *
  * @author jiachun.fjc
  */
-@SuppressWarnings("unused")
 public class StringBuilderHelper {
 
     private static final int MAX_BUF_SIZE;
     private static final ThreadLocal<StringBuilderHolder> HOLDER_THREAD_LOCAL;
 
     static {
-        MAX_BUF_SIZE = 1024 << 3;     // 8k
+        MAX_BUF_SIZE = 1024 << 3; // 8k
         HOLDER_THREAD_LOCAL = ThreadLocal.withInitial(StringBuilderHolder::new);
     }
 
@@ -38,11 +37,6 @@ public static StringBuilder get() {
         return holder.getStringBuilder();
     }
 
-    public static void truncate() {
-        StringBuilderHolder holder = HOLDER_THREAD_LOCAL.get();
-        holder.truncate();
-    }
-
     private static class StringBuilderHolder {
 
         private StringBuilder buf = new StringBuilder();

ingester-common/src/main/java/io/greptime/common/util/Strings.java

@@ -57,11 +57,13 @@ public static boolean isNullOrEmpty(String str) {
     /**
      * Checks if a string is whitespace, empty ("") or null.
      * <p>
+     * ``` java
      * Strings.isBlank(null)      = true
      * Strings.isBlank("")        = true
      * Strings.isBlank(" ")       = true
      * Strings.isBlank("bob")     = false
      * Strings.isBlank("  bob  ") = false
+     * ```
      */
     public static boolean isBlank(String str) {
         int strLen;
@@ -78,11 +80,13 @@ public static boolean isBlank(String str) {
     /**
      * Checks if a string is not empty (""), not null and not whitespace only.
      * <p>
+     * ``` java
      * Strings.isNotBlank(null)      = false
      * Strings.isNotBlank("")        = false
      * Strings.isNotBlank(" ")       = false
      * Strings.isNotBlank("bob")     = true
      * Strings.isNotBlank("  bob  ") = true
+     * ```
      */
     public static boolean isNotBlank(String str) {
         return !isBlank(str);
@@ -93,12 +97,14 @@ public static boolean isNotBlank(String str) {
      * <p>
      * A null input String returns null.
      * <p>
+     * ``` java
      * Strings.split(null, *)         = null
      * Strings.split("", *)           = []
      * Strings.split("a.b.c", '.')    = ["a", "b", "c"]
      * Strings.split("a..b.c", '.')   = ["a", "b", "c"]
      * Strings.split("a:b:c", '.')    = ["a:b:c"]
      * Strings.split("a b c", ' ')    = ["a", "b", "c"]
+     * ```
      */
     public static String[] split(String str, char separator) {
         return split(str, separator, false);
@@ -111,6 +117,7 @@ public static String[] split(String str, char separator) {
      * <p>
      * A null input String returns null.
      * <p>
+     * ``` java
      * Strings.split(null, *, true)         = null
      * Strings.split("", *, true)           = []
      * Strings.split("a.b.c", '.', true)    = ["a", "b", "c"]
@@ -122,6 +129,7 @@ public static String[] split(String str, char separator) {
      * Strings.split(" a b c", ' ', true)   = ["", a", "b", "c"]
      * Strings.split("  a b c", ' ', true)  = ["", "", a", "b", "c"]
      * Strings.split(" a b c ", ' ', true)  = ["", a", "b", "c", ""]
+     * ```
      */
     public static String[] split(String str, char separator, boolean preserveAllTokens) {
         if (str == null) {

ingester-common/src/main/java/io/greptime/common/util/SystemPropertyUtil.java

@@ -25,19 +25,10 @@
  * parse the values of the Java system properties.
  *
  */
-@SuppressWarnings("unused")
 public final class SystemPropertyUtil {
 
     private static final Logger LOG = LoggerFactory.getLogger(SystemPropertyUtil.class);
 
-    /**
-     * Returns {@code true} if and only if the system property
-     * with the specified {@code key} exists.
-     */
-    public static boolean contains(String key) {
-        return get(key) != null;
-    }
-
     /**
      * Returns the value of the Java system property with the
      * specified {@code key}, while falling back to {@code null}
@@ -155,6 +146,7 @@ public static int getInt(String key, int def) {
      * {@code def} if there's no such property or if access to
      * the specified property is not allowed.
      */
+    @SuppressWarnings("unused")
     public static long getLong(String key, long def) {
         String value = get(key);
         if (value == null) {
@@ -178,6 +170,7 @@ public static long getLong(String key, long def) {
      * Sets the value of the Java system property with the
      * specified {@code key}
      */
+    @SuppressWarnings("unused")
     public static Object setProperty(String key, String value) {
         return System.getProperties().setProperty(key, value);
     }