Add constructor for IntBuffer and CharBuffer

Author: patrickfav

CHANGELOG

@@ -4,6 +4,7 @@
 
 * add radix encoding/parsing and fix radix tests #6, #20
 * add support for Base32 RFC4648 non-hex alphabet encoding/parsing #21
+* add constructor for `IntBuffer` and `CharBuffer`
 
 ### Deprecations (will be removed in v1.0+)
 

src/main/java/at/favre/lib/bytes/Bytes.java

@@ -30,6 +30,7 @@
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
 import java.nio.CharBuffer;
+import java.nio.IntBuffer;
 import java.nio.ReadOnlyBufferException;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
@@ -371,14 +372,36 @@ public static Bytes from(double double8Byte) {
     }
 
     /**
-     * Creates a new instance from given ByteBuffer.
+     * Creates a new instance from given {@link ByteBuffer}.
      * Will use the same backing byte array and honour the buffer's byte order.
      *
-     * @param buffer to get the byte array from
+     * @param buffer to get the byte array from (must not be null)
      * @return new instance
      */
     public static Bytes from(ByteBuffer buffer) {
-        return wrap(buffer.array(), buffer.order());
+        return wrap(Objects.requireNonNull(buffer, "provided byte buffer must not be null").array(), buffer.order());
+    }
+
+    /**
+     * Creates a new instance from given {@link CharBuffer}.
+     * Will ignore buffer's byte order and use {@link ByteOrder#BIG_ENDIAN}
+     *
+     * @param buffer to get the char array from (must not be null)
+     * @return new instance
+     */
+    public static Bytes from(CharBuffer buffer) {
+        return from(Objects.requireNonNull(buffer, "provided char buffer must not be null").array());
+    }
+
+    /**
+     * Creates a new instance from given {@link IntBuffer}.
+     * Will ignore buffer's byte order and use {@link ByteOrder#BIG_ENDIAN}
+     *
+     * @param buffer to get the int array from (must not be null)
+     * @return new instance
+     */
+    public static Bytes from(IntBuffer buffer) {
+        return from(Objects.requireNonNull(buffer, "provided int buffer must not be null").array());
     }
 
     /**

src/test/java/at/favre/lib/bytes/BytesConstructorTests.java

@@ -26,10 +26,16 @@
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
 
-import java.io.*;
+import java.io.ByteArrayInputStream;
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.FileOutputStream;
 import java.math.BigInteger;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
+import java.nio.CharBuffer;
+import java.nio.IntBuffer;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.text.Normalizer;
@@ -188,6 +194,13 @@ public void fromIntArray() {
         assertArrayEquals(new byte[]{0, 11, 30, 55, 0, 0, 35, 53, 0, 0, 0, 0, 0, 0, 56, -70}, Bytes.from(728631, 9013, 0, 14522).array());
     }
 
+    @Test
+    public void fromIntBuffer() {
+        assertArrayEquals(new byte[]{0, 0, 0, 1, 0, 0, 0, 2}, Bytes.from(IntBuffer.wrap(new int[]{1, 2})).array());
+        assertArrayEquals(Bytes.from(Bytes.from(871193), Bytes.from(6761), Bytes.from(-917656)).array(), Bytes.from(IntBuffer.wrap(new int[]{871193, 6761, -917656})).array());
+        assertArrayEquals(Bytes.empty().array(), Bytes.from(IntBuffer.allocate(0)).array());
+    }
+
     @Test
     public void fromLong() {
         long test = 172283719283L;
@@ -281,6 +294,7 @@ public void fromCharArray() {
         assertArrayEquals(String.valueOf(s1.toCharArray()).getBytes(StandardCharsets.ISO_8859_1), Bytes.from(s1.toCharArray(), StandardCharsets.ISO_8859_1).array());
         assertArrayEquals(String.valueOf(s1.toCharArray()).getBytes(StandardCharsets.UTF_16), Bytes.from(s1.toCharArray(), StandardCharsets.UTF_16).array());
         assertArrayEquals(String.valueOf(s1.toCharArray()).getBytes(StandardCharsets.UTF_8), Bytes.from(s1.toCharArray(), StandardCharsets.UTF_8).array());
+        assertArrayEquals(Bytes.empty().array(), Bytes.from(CharBuffer.allocate(0)).array());
     }
 
     @Test
@@ -306,8 +320,10 @@ private void checkString(String string, Charset charset) {
     private void checkCharArray(String s) {
         Bytes b1 = Bytes.from(s.toCharArray());
         Bytes b2 = Bytes.from(s.toCharArray(), StandardCharsets.UTF_8);
+        Bytes b3 = Bytes.from(CharBuffer.wrap(s.toCharArray()));
         assertArrayEquals(String.valueOf(s.toCharArray()).getBytes(StandardCharsets.UTF_8), b1.array());
         assertArrayEquals(String.valueOf(s.toCharArray()).getBytes(StandardCharsets.UTF_8), b2.array());
+        assertArrayEquals(String.valueOf(s.toCharArray()).getBytes(StandardCharsets.UTF_8), b3.array());
     }
 
     @Test