Java Code Examples for com.google.common.base.Defaults#defaultValue()

@Test
public void allBuilderMethodsReturnThis() throws Exception {
  for (Method method : ManagedChannelBuilder.class.getDeclaredMethods()) {
    if (Modifier.isStatic(method.getModifiers()) || Modifier.isPrivate(method.getModifiers())) {
      continue;
    }
    if (method.getName().equals("build")) {
      continue;
    }
    Class<?>[] argTypes = method.getParameterTypes();
    Object[] args = new Object[argTypes.length];
    for (int i = 0; i < argTypes.length; i++) {
      args[i] = Defaults.defaultValue(argTypes[i]);
    }
    if (method.getName().equals("maxInboundMetadataSize")) {
      args[0] = 1; // an arbitrary positive number
    }

    Object returnedValue = method.invoke(testChannelBuilder, args);

    assertThat(returnedValue).isSameAs(testChannelBuilder);
  }
}
 

/**
 * Clears all fields that match a particular predicate. For all primitive types, the value is set
 * to zero. For object types, the value is set to null.
 *
 * @param predicate
 */
private void clear(Predicate<Field> predicate, boolean isSecret) {
  try {
    for(Field field : FieldUtils.getAllFields(getClass())) {
      if(predicate.apply(field)) {
        if (isSecret && field.getType().equals(String.class)) {
          final String value = (String) field.get(this);

          if (Strings.isNullOrEmpty(value)) {
            field.set(this, null);
          } else {
            field.set(this, USE_EXISTING_SECRET_VALUE);
          }
        } else {
          Object defaultValue = Defaults.defaultValue(field.getType());
          field.set(this, defaultValue);
        }
      }
    }
  } catch (IllegalAccessException e) {
    throw Throwables.propagate(e);
  }
}
 

/**
 * this nullifies and resets transient values that are supposed not to be stored
 *
 * @param zeObject The object where non transient fields will be nullified.
 */
void resetTransientValues(Object zeObject) {
    if (zeObject != null) {
        Field[] fields = zeObject.getClass().getDeclaredFields();
        for (Field field : fields) {
            // ignore jacoco injected field
            if (Modifier.isTransient(field.getModifiers()) && !field.getName().endsWith("jacocoData")) { //$NON-NLS-1$
                Object defaultValue = Defaults.defaultValue(field.getType());
                field.setAccessible(true);
                try {
                    field.set(zeObject, defaultValue);
                } catch (IllegalArgumentException | IllegalAccessException e) {
                    LOG.error("failed to reset the transient field [" + field + "] before storage", e);
                }
            }
        }
    } // else null so do nothing
}
 

@Test
public void allBuilderMethodsReturnThis() throws Exception {
  for (Method method : ManagedChannelBuilder.class.getDeclaredMethods()) {
    if (Modifier.isStatic(method.getModifiers()) || Modifier.isPrivate(method.getModifiers())) {
      continue;
    }
    if (method.getName().equals("build")) {
      continue;
    }
    Class<?>[] argTypes = method.getParameterTypes();
    Object[] args = new Object[argTypes.length];
    for (int i = 0; i < argTypes.length; i++) {
      args[i] = Defaults.defaultValue(argTypes[i]);
    }
    if (method.getName().equals("maxInboundMetadataSize")) {
      args[0] = 1; // an arbitrary positive number
    }

    Object returnedValue = method.invoke(testChannelBuilder, args);

    assertThat(returnedValue).isSameInstanceAs(testChannelBuilder);
  }
}
 

/**
 * 具有一定兼容性的类型转换/切换
 * 将一个未知类型转化为你想要的那个类型，它会宽容地做转换，比如map映射成bean，bean映射成map
 * list的第一个元素映射成bean，list的第一个元素映射成map等等。
 * 如果入参是null，那么返回结果也是null
 *
 * @param nonCollectionType 目标类型，不允许是集合类型
 */
@SuppressWarnings("all")
private static <T> T toNonCollectionType(Object data, Class<T> nonCollectionType) {
    if (Collection.class.isAssignableFrom(nonCollectionType)) {
        throw new RuntimeException("API使用错误，本方法不支持将目标对象转为非集合类型");
    }
    if (data == null) {
        return Defaults.defaultValue(nonCollectionType);
    }
    if (data.getClass().isArray()) {
        data = ArrayUtil.toList(data);
    }
    if (data instanceof Collection) {
        Collection collection = (Collection) data;
        if (nonCollectionType == String.class) {
            return (T) JSON.toJSONString(collection);
        }
        if (collection.isEmpty()) {
            return null;
        }
        if (collection.size() >= 2) {
            LOG.warn(new Throwable(String.format("集合 【 %s 】  的元素个数不只一个,我们只取出第一个做转换", data)));
        }
        for (Object element : collection) {
            LOG.debug("集合的第一个元素会被转为目标类型");
            return transferNonCollection(element, nonCollectionType);
        }
    } else {
        return transferNonCollection(data, nonCollectionType);
    }
    throw castFailedException(data, nonCollectionType);
}
 

private Object createDefaultParamValue(Class<?> clazz) {
  if (clazz.isPrimitive())
    return Defaults.defaultValue(clazz);
  if (byte[].class.equals(clazz))
    return "FOO".getBytes();
  return null;
}
 

public AbstractParamProcessor(String paramPath, JavaType targetType, Object defaultValue, boolean required) {
  this.paramPath = paramPath;
  this.targetType = targetType;
  this.defaultValue = defaultValue;
  this.required = required;
  if (defaultValue == null &&
      targetType != null && targetType.getRawClass().isPrimitive()) {
    this.defaultValue = Defaults.defaultValue(targetType.getRawClass());
  }
}
 

@Override
public Object invoke(Object object, Method method, Object[] args) throws Throwable {
  OperationId operationId = operations.get(method);
  if (operationId != null) {
    future.set(session.execute(PrimitiveOperation.operation(operationId, encode(args)))
        .thenApply(DefaultProxySession.this::decode));
  } else {
    throw new PrimitiveException("Unknown primitive operation: " + method.getName());
  }
  return Defaults.defaultValue(method.getReturnType());
}
 

@Nullable
private Object getDefaultValue(@NotNull Class<?> type) {
    if (type == com.google.common.base.Optional.class) {
        // If it's Guava optional then handle it as an absent value
        return com.google.common.base.Optional.absent();
    } else if (type == java.util.Optional.class) {
        // If it's Java optional then handle it as an absent value
        return java.util.Optional.empty();
    } else if (type.isPrimitive()) {
        // If parameter is a primitive set the appropriate default value
        return Defaults.defaultValue(type);
    }
    return null;
}
 

@Override
public Object invoke(Object self, Method thisMethod, Method proceed, Object[] args) throws Throwable {
    OutlineImpl.this.lastInvokedMethod.set(thisMethod.getName());
    return Defaults.defaultValue(thisMethod.getReturnType());
}