Java Code Examples for java.lang.reflect.Field

private void addIncommingRef (Object to, Object from, Field f) {
    // wrap statics with special (private) object
    Object save = from != null ? from : Root.createStatic(f, to);

    Object entry = objects.get(to);
    if (entry == null) {
        if (save instanceof Object[]) {
            entry= new Object[] { save };
        } else {
            entry = save;
        }
    } else if (! (entry instanceof Object[])) {
            entry = new Object[] { entry, save };
    } else {
        int origLen = ((Object[])entry).length;
        Object[] ret = new Object[origLen + 1];
        System.arraycopy(entry, 0, ret, 0, origLen);
        ret[origLen] = save;
        entry = ret;
    }
    objects.put(to, entry);
}
 

public static void autoFindAndInjectFields(Object inst, Map properties){
		Collection<Field> fields = ReflectUtils.findFieldsFilterStatic(inst.getClass());
		if(fields==null || fields.isEmpty())
			return ;
//		Map properties = M.c(objects);
		for(Field f :fields){
			if(properties.containsKey(f.getName())){
				ReflectUtils.setBeanFieldValue(f, inst, properties.get(f.getName()));
				continue;
			}
			if(properties.containsKey(f.getType())){
				ReflectUtils.setBeanFieldValue(f, inst, properties.get(f.getType()));
				continue;
			}
		}
	}
 

/**
 * Adds a default size for the given jdbc type.
 * 
 * @param jdbcTypeName The name of the jdbc type, one of the {@link Types} constants
 * @param defaultSize  The default size
 */
public void setDefaultSize(String jdbcTypeName, int defaultSize)
{
    try
    {
        Field constant = Types.class.getField(jdbcTypeName);

        if (constant != null)
        {
            setDefaultSize(constant.getInt(null), defaultSize);
        }
    }
    catch (Exception ex)
    {
        // ignore -> won't be defined
        _log.warn("Cannot add default size for undefined jdbc type "+jdbcTypeName, ex);
    }
}
 

@SuppressWarnings ( {
    "rawtypes", "unchecked"
} )
public static TreeMap<Object, Object> makeTreeMap ( Object tgt, Comparator comparator ) throws Exception {
    TreeMap<Object, Object> tm = new TreeMap<>(comparator);

    Class<?> entryCl = Class.forName("java.util.TreeMap$Entry");
    Constructor<?> entryCons = entryCl.getDeclaredConstructor(Object.class, Object.class, entryCl);
    entryCons.setAccessible(true);
    Field leftF = Reflections.getField(entryCl, "left");

    Field rootF = Reflections.getField(TreeMap.class, "root");
    Object root = entryCons.newInstance(tgt, tgt, null);
    leftF.set(root, entryCons.newInstance(tgt, tgt, root));
    rootF.set(tm, root);
    Reflections.setFieldValue(tm, "size", 2);
    return tm;
}
 

/**
 * Uses reflection to access divider private attribute and override its color
 * Use Color.Transparent if you wish to hide them
 */
public void setSeparatorColor(int separatorColor) {
    mSeparatorColor = separatorColor;

    Field[] pickerFields = NumberPicker.class.getDeclaredFields();
    for (Field pf : pickerFields) {
        if (pf.getName().equals("mSelectionDivider")) {
            pf.setAccessible(true);
            try {
                pf.set(this, new ColorDrawable(separatorColor));
            } catch (IllegalAccessException | IllegalArgumentException e) {
                e.printStackTrace();
            }
            break;
        }
    }
}
 

/**
 * Gets all entries from the specified class or its super-classes that have
 * been annotated with annotation provided.
 *
 * @param cls Class in which search for methods.
 * @param annCls Annotation.
 * @return Set of entries with given annotations.
 */
private Iterable<Field> fieldsWithAnnotation(Class<?> cls, Class<? extends Annotation> annCls) {
    assert cls != null;
    assert annCls != null;

    Collection<Field> fields = fieldsFromCache(cls, annCls);

    if (fields == null) {
        fields = new ArrayList<>();

        for (Field field : cls.getDeclaredFields()) {
            Annotation ann = field.getAnnotation(annCls);

            if (ann != null || needsRecursion(field))
                fields.add(field);
        }

        cacheFields(cls, annCls, fields);
    }

    return fields;
}
 

/**
 * @param controller
 * 		Window context.
 *
 * @return main window instance.
 */
public static MainWindow get(GuiController controller) {
	if(window == null) {
		MainWindow app = window = new MainWindow(controller);
		PlatformImpl.startup(() -> {
           	Stage stage = new Stage();
           	try {
				Field field = Stage.class.getDeclaredField("primary");
				field.setAccessible(true);
				field.setBoolean(stage, true);
           		app.init();
               	app.start(stage);
               } catch (Exception ex) {
           		throw new RuntimeException(ex);
           	}
			// Disable CSS logger, it complains a lot about non-issues
			try {
				ManagementFactory.getPlatformMXBean(PlatformLoggingMXBean.class)
						.setLoggerLevel("javafx.css", "OFF");
			} catch (IllegalArgumentException ignored) {
				// Expected: logger may not exist
			}
		});
	}
	return window;
}
 

@Override
public void scan(JCTree tree) {
    if (tree == null ||
            excludeTags.contains(treeUtil.nameFromTag(tree.getTag()))) {
        return;
    }

    Info self = new Info(tree, endPosTable);
    if (mandatoryType(tree)) {
        check(tree.type != null,
                "'null' field 'type' found in tree ", self);
        if (tree.type==null)
            new Throwable().printStackTrace();
    }

    Field errField = checkFields(tree);
    if (errField!=null) {
        check(false,
                "'null' field '" + errField.getName() + "' found in tree ", self);
    }

    Info prevEncl = encl;
    encl = self;
    tree.accept(this);
    encl = prevEncl;
}
 

/**
 * 繰り返しのアノテーションが1つの場合の展開
 */
@Test
public void testExpand_repeatSingle() {
    
    Field field = getSampleField("repeatSingle");
    
    Annotation targetAnno = field.getAnnotation(CsvLengthMax.class);
    
    List<ExpandedAnnotation> actual = expander.expand(targetAnno);
    
    assertThat(actual).hasSize(1);
    
    {
        ExpandedAnnotation expandedAnno = actual.get(0);
        assertThat(expandedAnno.getOriginal()).isInstanceOf(CsvLengthMax.class);
        assertThat(expandedAnno.getIndex()).isEqualTo(0);
        assertThat(expandedAnno.isComposed()).isEqualTo(false);
        assertThat(expandedAnno.getChilds()).isEmpty();
    }
    
}
 

private static boolean isDefaultValue(final Field field, final Object value) {
    Class<?> clazz = field.getType();
    if (int.class.equals(clazz) || Integer.class.equals(clazz)) {
        return (int) value == 0;
    } else if (byte.class.equals(clazz) || Byte.class.equals(clazz)) {
        return (byte) value == 0;
    } else if (long.class.equals(clazz) || Long.class.equals(clazz)) {
        return (long) value == 0L;
    } else if (double.class.equals(clazz) || Double.class.equals(clazz)) {
        return (double) value == 0.0d;
    } else if (float.class.equals(clazz) || Float.class.equals(clazz)) {
        return (float) value == 0.0f;
    } else if (short.class.equals(clazz) || Short.class.equals(clazz)) {
        return (short) value == 0;
    } else if (boolean.class.equals(clazz) || Boolean.class.equals(clazz)) {
        return !((boolean) value);
    } else if (String.class.equals(clazz)) {
        return null == value || "".equals(value);
    }
    return false;
}
 

private void enableOpenSSLEngineImplAlpn() throws NoSuchFieldException, IllegalAccessException {
    Field sslParametersField = mSSLEngine.getClass().getDeclaredField("sslParameters");
    sslParametersField.setAccessible(true);
    Object sslParameters = sslParametersField.get(mSSLEngine);
    if (sslParameters == null) {
        throw new IllegalAccessException("sslParameters value is null");
    }
    Field useSessionTicketsField = sslParameters.getClass().getDeclaredField("useSessionTickets");
    useSessionTicketsField.setAccessible(true);
    useSessionTicketsField.set(sslParameters, true);
    Field useSniField = sslParameters.getClass().getDeclaredField("useSni");
    useSniField.setAccessible(true);
    useSniField.set(sslParameters, true);
    Field alpnProtocolsField = sslParameters.getClass().getDeclaredField("alpnProtocols");
    alpnProtocolsField.setAccessible(true);
    alpnProtocolsField.set(sslParameters, concatLengthPrefixed(mClientAlpns));
}
 

@Test
public void testRestoreSerializerWithSameFields() {
	final PojoSerializerSnapshot<TestPojo> testSnapshot = buildTestSnapshot(Arrays.asList(
		ID_FIELD,
		NAME_FIELD,
		HEIGHT_FIELD
	));

	final TypeSerializer<TestPojo> restoredSerializer = testSnapshot.restoreSerializer();
	assertSame(restoredSerializer.getClass(), PojoSerializer.class);
	final PojoSerializer<TestPojo> restoredPojoSerializer = (PojoSerializer<TestPojo>) restoredSerializer;

	final Field[] restoredFields = restoredPojoSerializer.getFields();
	assertArrayEquals(
		new Field[] { ID_FIELD.field, NAME_FIELD.field, HEIGHT_FIELD.field },
		restoredFields);

	final TypeSerializer<?>[] restoredFieldSerializers = restoredPojoSerializer.getFieldSerializers();
	assertArrayEquals(
		new TypeSerializer[] { IntSerializer.INSTANCE, StringSerializer.INSTANCE, DoubleSerializer.INSTANCE },
		restoredFieldSerializers);
}
 

@Override
public void onLoad(final ItemGroup<? extends Item> parent, final String name) throws IOException {
    try {
        final Field parentField = AbstractItem.class.getDeclaredField("parent");
        parentField.setAccessible(true);
        ReflectionUtils.setField(parentField, this, parent);
    } catch (final Exception e) {
        throw new RuntimeException(e);
    }

    doSetName(name);
    if (this.transientActions == null) {
        this.transientActions = new Vector<>();
    }
    updateTransientActions();
    getBuildersList().setOwner(this);
    getPublishersList().setOwner(this);
    getBuildWrappersList().setOwner(this);

    initRepos();
}
 

@Test
public void getRowType() throws Exception {
    Field f1 = BaseClass.class.getField("f1");
    Field f2 = BaseClass.class.getField("f2");
    Field f3 = BaseClass.class.getField("f3");
    Field f4 = ConcreteClass.class.getField("f4");
    Field f5 = ConcreteClass.class.getField("f5");
    Field array1 = BaseClass.class.getField("array1");

    assertEquals(String.class, ReflectionUtil.getRawType(f1.getGenericType(), ConcreteClass.class));
    assertEquals(Integer.class, ReflectionUtil.getRawType(f2.getGenericType(), ConcreteClass.class));
    assertEquals(String.class, ReflectionUtil.getRawType(f3.getGenericType(), ConcreteClass.class));
    assertEquals(Long.class, ReflectionUtil.getRawType(f4.getGenericType(), ConcreteClass.class));
    assertEquals(List.class, ReflectionUtil.getRawType(f5.getGenericType(), ConcreteClass.class));
    assertEquals(String[].class, ReflectionUtil.getRawType(array1.getGenericType(), ConcreteClass.class));

    assertEquals(Object.class, ReflectionUtil.getRawType(f1.getGenericType()));
}
 

@Test
public void getCreatesSenderWithCorrectDatabaseName() throws Exception {
    final MetricsInfluxDbReporterConfiguration configuration = new MetricsInfluxDbReporterConfiguration() {
        @Override
        public URI getUri() {
            return URI.create("udp://127.0.0.1:8086/data_base_1");
        }
    };
    final InfluxDbSenderProvider provider = new InfluxDbSenderProvider(configuration);
    final InfluxDbSender influxDbSender = provider.get();

    final Field field = Class.forName("com.izettle.metrics.influxdb.InfluxDbBaseSender").getDeclaredField("influxDbWriteObject");
    field.setAccessible(true);
    final InfluxDbWriteObject influxDbWriteObject = (InfluxDbWriteObject) field.get(influxDbSender);
    assertEquals("data_base_1", influxDbWriteObject.getDatabase());
}
 

private static Component getTipWindow() {
    try {
        Field tipWindowField = ToolTipManager.class.getDeclaredField("tipWindow");

        tipWindowField.setAccessible(true);

        Popup value = (Popup) tipWindowField.get(ToolTipManager.sharedInstance());

        Field componentField = Popup.class.getDeclaredField("component");

        componentField.setAccessible(true);

        return (Component) componentField.get(value);
    } catch (Exception e) {
        throw new RuntimeException("getToolTipComponent failed", e);
    }
}
 

private static String tryGetID(org.openide.nodes.Node node) {
    // TODO: Request API to be able to access org.netbeans.modules.html.navigator.Description from the Node's lookup
    // Reading attributes from HTMLElementNode
    try {
        Field sourceField = node.getClass().getDeclaredField("source");
        sourceField.setAccessible(true);
        Object source = sourceField.get(node);
        Method getAttributes = source.getClass().getDeclaredMethod("getAttributes");
        getAttributes.setAccessible(true);
        Object attributesObj = getAttributes.invoke(source);
        Map<String, String> attributes = (Map<String, String>) attributesObj;
        return attributes.get("id");
    } catch (Exception ex) {
        LOG.log(Level.INFO, "Problem while getting id from node "+node+", class = "+node.getClass()+": "+ex.toString());
        return null;
    }
}
 

private void singalQueue(PriorityMessageQueue queue) throws Exception {
    Field lock = null;
    Class<?> queueType = queue.getClass();

    while (queueType != null && lock == null) {
        try {
            lock = queueType.getDeclaredField("lock");
        } catch (NoSuchFieldException error) {
            queueType = queueType.getSuperclass();
            if (Object.class.equals(queueType)) {
                queueType = null;
            }
        }
    }

    assertNotNull("MessageQueue implementation unknown", lock);
    lock.setAccessible(true);

    Object lockView = lock.get(queue);

    synchronized (lockView) {
        lockView.notify();
    }
}
 

public static Response copyResponseIfNeeded(Response response) {
    if (!(response instanceof ResponseImpl)) {
        Response r = fromResponse(response).build();
        Field[] declaredFields = ReflectionUtil.getDeclaredFields(response.getClass());
        for (Field f : declaredFields) {
            Class<?> declClass = f.getType();
            if (declClass == Annotation[].class) {
                try {
                    Annotation[] fieldAnnotations =
                        ReflectionUtil.accessDeclaredField(f, response, Annotation[].class);
                    ((ResponseImpl)r).setEntityAnnotations(fieldAnnotations);
                } catch (Throwable ex) {
                    LOG.warning("Custom annotations if any can not be copied");
                }
                break;
            }
        }
        return r;
    }
    return response;
}
 

@Test
public void testLoadPrivateKeyBase64() throws Exception {
    try {
        String paramsStr = new String(Files.readAllBytes(Paths.get("./src/test/resources/authParams.json")));

        // load privatekey and encode it using base64
        ObjectMapper jsonMapper = ObjectMapperFactory.create();
        Map<String, String> authParamsMap = jsonMapper.readValue(paramsStr,
                new TypeReference<HashMap<String, String>>() {
                });
        String privateKeyContents = new String(Files.readAllBytes(Paths.get(authParamsMap.get("privateKey"))));
        authParamsMap.put("privateKey", "data:application/x-pem-file;base64,"
                + new String(Base64.getEncoder().encode(privateKeyContents.getBytes())));

        AuthenticationAthenz authBase64 = new AuthenticationAthenz();
        authBase64.configure(jsonMapper.writeValueAsString(authParamsMap));

        PrivateKey privateKey = Crypto.loadPrivateKey(new File("./src/test/resources/tenant_private.pem"));
        Field field = authBase64.getClass().getDeclaredField("privateKey");
        field.setAccessible(true);
        PrivateKey key = (PrivateKey) field.get(authBase64);
        assertEquals(key, privateKey);
    } catch (Exception e) {
        Assert.fail();
    }
}
 

@Override
public boolean isValid(final Object value, final ConstraintValidatorContext context) {
  for (final String fieldName : fields) {
    try {
      final Field field = value.getClass().getDeclaredField(fieldName);
      field.setAccessible(true);

      if (StringUtils.isEmpty((String) field.get(value))) {
        return true;
      }

      final String certificate = (String) field.get(value);
      if (certificate.getBytes(UTF_8).length > 7000) {
        return false;
      }

    } catch (final NoSuchFieldException | IllegalAccessException e) {
      throw new RuntimeException(e);
    }
  }
  return true;
}
 

/**
 * 获取全部的Field
 *
 * @param entityClass
 * @param fieldList
 * @return
 */
private static List<Field> getAllField(Class<?> entityClass, List<Field> fieldList) {
    if (fieldList == null) {
        fieldList = new ArrayList<Field>();
    }
    if (entityClass.equals(Object.class)) {
        return fieldList;
    }
    Field[] fields = entityClass.getDeclaredFields();
    for (Field field : fields) {
        // 排除静态字段
        if (!Modifier.isStatic(field.getModifiers())) {
            fieldList.add(field);
        }
    }
    Class<?> superClass = entityClass.getSuperclass();
    if (superClass != null && !superClass.equals(Object.class)
            && (!Map.class.isAssignableFrom(superClass)
            && !Collection.class.isAssignableFrom(superClass))) {
        return getAllField(entityClass.getSuperclass(), fieldList);
    }
    return fieldList;
}
 

/**
 * Creates an attribute which reads values from the field indicated using reflection.
 *
 * @param objectType The type of the object containing the field
 * @param fieldType The type of the field in the object
 * @param fieldName The name of the field
 */
public ReflectiveAttribute(Class<O> objectType, Class<A> fieldType, String fieldName) {
    super(objectType, fieldType, fieldName);
    Field field;
    try {
        field = getField(objectType, fieldName);
        if (!field.isAccessible()) {
            field.setAccessible(true);
        }
    }
    catch (Exception e) {
        throw new IllegalStateException("Invalid attribute definition: No such field '" + fieldName + "' in object '" + objectType.getName() + "'");
    }
    if (!fieldType.isAssignableFrom(field.getType())) {
        throw new IllegalStateException("Invalid attribute definition: The type of field '" + fieldName + "', type '" + field.getType() + "', in object '" + objectType.getName() + "', is not assignable to the type indicated: " + fieldType.getName());
    }
    this.field = field;
}
 

public static void writeField(final Object target, final Object value, String obfName, String deobfName) {
	if (target == null) return;
	
	final Class<?> cls = target.getClass();
       final Field field = getField(cls, obfName, deobfName);
       
       if (field == null) return;
       
       if (!field.isAccessible()) {
           field.setAccessible(true);
       }
       
       try {
		field.set(target, value);
	} catch (Exception e) {}
       
}
 

private <T extends PageObject> void tryToWaitOnPageObjectsVisibility(T pageInstance, Field field) {
    try {
        waitOnPageObjectsVisibility(pageInstance, field);
    } catch (TimeoutException e) {
        throw exception(pageInstance, e).whenWaitingForVisibilityOfPageObjectField(field);
    }
}
 

private Field getField(Class<?> clazz, String name) {
    try {
        return clazz.getField(name);
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}
 

protected Result validDeleteTx(int chainId, DeleteContractTransaction tx) {
    try {
        DeleteContractTxValidator validator = new DeleteContractTxValidator();
        Field field = DeleteContractTxValidator.class.getDeclaredField("contractHelper");
        field.setAccessible(true);
        field.set(validator, contractHelper);
        return validator.validate(chainId, tx);
    } catch (Exception e) {
        Log.error(e);
        return getFailed();
    }
}
 

/**
 * 初始化组件列表
 */
private void initComponents() throws InstantiationException, IllegalAccessException {
    // 获取需要扫描的包名
    String pkgName = getPackage();

    // 获取包下所有类
    List<Class<?>> classes = ClassUtil.getClasses(pkgName);
    if (CollectionUtils.isEmpty(classes)) {
        return;
    }

    // 遍历类
    for (Class clazz : classes) {
        Field[] fields = clazz.getDeclaredFields();
        if (fields==null || fields.length==0) {
            continue;
        }

        // 遍历成员变量
        for (Field field : fields) {
            // 获取Field上的@InjectComponents注解
            InjectComponents injectComponents = AnnotationUtil.getAnnotationValueByField(field, InjectComponents.class);
            if (injectComponents == null) {
                continue;
            }

            // 创建componentList对象
            List<BaseComponent> componentList = initComponentList(injectComponents);

            // 赋值
            setValueForField(clazz, field, componentList);
        }
    }

}
 

public static final Field findFieldIfExists(Class clazz, String fieldName) {
    if (clazz == null) {
        return null;
    }
    Field field = null;
    try {
        field = clazz.getField(fieldName);
    } catch (Error | Exception e) {
    }
    return field;
}
 

@Test
public void testGetValeOfAPrivateFieldUsingFieldObject() throws Exception {
    // GIVEN
    privateField = 10l;
    final Field toi = getClass().getDeclaredField("privateField");

    // WHEN
    final Object value = ReflectionUtils.getValue(this, toi);

    // THEN
    assertThat(privateField, equalTo(value));
}