[java] add new method to get char arrays as string in decoders.

[java] add new method to put char arrays from string in encoders.

Author: avaiss

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/java/JavaGenerator.java

@@ -1621,6 +1621,23 @@ private CharSequence generatePrimitiveArrayPropertyDecode(final String propertyN
  fieldLength,
  generateArrayFieldNotPresentCondition(token.version(), indent),
  offset));
+
+ sb.append(String.format(
+ "\n" +
+ indent + " public String %s()\n" +
+ indent + " {\n" +
+ "%s" +
+ indent + " final byte[] dst = new byte[%d];\n" +
+ indent + " buffer.getBytes(this.offset + %d, dst, 0, %d);\n\n" +
+ indent + " int end = 0;\n" +
+ indent + " for (; end < %d && dst[end] != 0; ++end);\n\n" +
+ indent + " return new String(dst, 0, end, %s);\n" +
+ indent + " }\n\n",
+ formatPropertyName(propertyName),
+ generateStringNotPresentCondition(token.version(), indent),
+ fieldLength, offset,
+ fieldLength, fieldLength,
+ charset(encoding.characterEncoding())));
  }
 
  return sb;
@@ -1695,6 +1712,30 @@ private CharSequence generatePrimitiveArrayPropertyEncode(
  toUpperFirstChar(propertyName),
  fieldLength,
  offset));
+
+ sb.append(String.format(
+ indent + " public %s put%s(final String src)\n" +
+ indent + " {\n" +
+ indent + " final int length = %d;\n" +
+ indent + " final byte[] bytes = src.getBytes(%s);\n" +
+ indent + " if (bytes.length > length)\n" +
+ indent + " {\n" +
+ indent + " throw new IndexOutOfBoundsException(" +
+ "\"string too large for copy: byte length=\" + bytes.length);\n" +
+ indent + " }\n\n" +
+ indent + " buffer.putBytes(this.offset + %d, bytes, 0, bytes.length);\n\n" +
+ indent + " for (int start = bytes.length; start < length; ++start)\n" +
+ indent + " {\n" +
+ indent + " buffer.putByte(this.offset + %d + start, (byte) 0);\n" +
+ indent + " }\n\n" +
+ indent + " return this;\n" +
+ indent + " }\n",
+ formatClassName(containingClassName),
+ toUpperFirstChar(propertyName),
+ fieldLength,
+ charset(encoding.characterEncoding()),
+ offset,
+ offset));
  }
 
  return sb;

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/java/JavaUtil.java

@@ -19,7 +19,12 @@
 import uk.co.real_logic.sbe.SbeTool;
 import uk.co.real_logic.sbe.util.ValidationUtil;
 
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.EnumMap;
+import java.util.HashMap;
 import java.util.Map;
 
 /**
@@ -83,6 +88,30 @@ public String toString()
  TYPE_NAME_BY_PRIMITIVE_TYPE_MAP.put(PrimitiveType.DOUBLE, "double");
  }
 
+ /** Indexes known charset aliases to the name of the instance in {@link StandardCharsets}. */
+ private static final Map<String, String> STD_CHARSETS = new HashMap<>();
+
+ static
+ {
+ try
+ {
+ for (Field f : StandardCharsets.class.getDeclaredFields())
+ {
+ if (Charset.class.isAssignableFrom(f.getType())
+ && ((f.getModifiers() & Modifier.STATIC) == Modifier.STATIC))
+ {
+ final Charset c = (Charset) f.get(null);
+ STD_CHARSETS.put(c.name(), f.getName());
+ c.aliases().forEach(alias -> STD_CHARSETS.put(alias, f.getName()));
+ }
+ }
+ }
+ catch (IllegalAccessException e)
+ {
+ throw new RuntimeException(e);
+ }
+ }
+
  /**
  * Map the name of a {@link uk.co.real_logic.sbe.PrimitiveType} to a Java primitive type name.
  *
@@ -168,4 +197,22 @@ public static void append(final StringBuilder builder, final String indent, fina
  {
  builder.append(indent).append(line).append('\n');
  }
+
+ /**
+ * Return java code to fetch an instance of {@link java.nio.charset.Charset} corresponding to the given encoding.
+ * @param encoding the encoding (eg. UTF-8).
+ * @return the code to fetch the assiciated charset.
+ */
+ public static String charset(String encoding)
+ {
+ final String charset = STD_CHARSETS.get(encoding);
+ if (charset != null)
+ {
+ return "java.nio.charset.StandardCharsets." + charset;
+ }
+ else
+ {
+ return "java.nio.charset.Charset.forName(\"" + encoding + "\")";
+ }
+ }
 }

sbe-tool/src/test/java/uk/co/real_logic/sbe/generation/java/JavaGeneratorTest.java

@@ -351,6 +351,25 @@ public void shouldGenerateEnumCodecs() throws Exception
  assertThat(get(decoder, "code"), hasToString("B"));
  }
 
+ @Test
+ public void shouldGenerateGetString() throws Exception
+ {
+ final UnsafeBuffer buffer = new UnsafeBuffer(new byte[4096]);
+ generator().generate();
+
+ final Object encoder = wrap(buffer, compileCarEncoder().newInstance());
+ final Object decoder = getCarDecoder(buffer, encoder);
+
+ putString(encoder, "vehicleCode", "R11");
+ assertThat(get(decoder, "vehicleCode"), is("R11"));
+
+ putString(encoder, "vehicleCode", "");
+ assertThat(get(decoder, "vehicleCode"), is(""));
+
+ putString(encoder, "vehicleCode", "R11R12");
+ assertThat(get(decoder, "vehicleCode"), is("R11R12"));
+ }
+
  private Class<?> getModelClass(final Object encoder) throws ClassNotFoundException
  {
  final String className = "Model";

sbe-tool/src/test/java/uk/co/real_logic/sbe/generation/java/ReflectionUtil.java

@@ -15,6 +15,8 @@
  */
 package uk.co.real_logic.sbe.generation.java;
 
+import static uk.co.real_logic.sbe.generation.java.JavaUtil.toUpperFirstChar;
+
 public final class ReflectionUtil
 {
  static int getSbeSchemaVersion(final Object encoder) throws Exception
@@ -122,4 +124,9 @@ static int getCount(Object groupFlyweight) throws Exception
  {
  return getInt(groupFlyweight, "count");
  }
+
+ static void putString(Object object, String name, String value) throws Exception
+ {
+ object.getClass().getMethod("put" + toUpperFirstChar(name), String.class).invoke(object, value);
+ }
 }