fix cod

hutool-core/src/main/java/cn/hutool/core/lang/func/LambdaInfo.java

@@ -1,5 +1,6 @@
 package cn.hutool.core.lang.func;
 
+import cn.hutool.core.bean.BeanUtil;
 import cn.hutool.core.classloader.ClassLoaderUtil;
 import cn.hutool.core.lang.Assert;
 import cn.hutool.core.text.StrPool;
@@ -11,28 +12,42 @@ import java.lang.reflect.Method;
 import java.lang.reflect.Type;
 
 /**
- * 存放lambda信息
+ * 存放lambda信息<br>
+ * 此类是{@link SerializedLambda}信息的扩充和补充类，包括：
+ * <ul>
+ *     <li>实例化后的对象方法参数类型，一般用于方法引用</li>
+ * </ul>
  *
  * @author VampireAchao
  */
 public class LambdaInfo {
 
 	private static final Type[] EMPTY_TYPE = new Type[0];
+	// 实例对象的方法参数类型
 	private final Type[] instantiatedMethodParameterTypes;
+	// 方法或构造的参数类型
 	private final Type[] parameterTypes;
 	private final Type returnType;
+	// 方法名或构造名称
 	private final String name;
 	private final Executable executable;
 	private final Class<?> clazz;
 	private final SerializedLambda lambda;
 
+	/**
+	 * 构造
+	 *
+	 * @param executable 构造对象{@link Constructor}或方法对象{@link Method}
+	 * @param lambda     实现了序列化接口的lambda表达式
+	 */
 	public LambdaInfo(final Executable executable, final SerializedLambda lambda) {
+		Assert.notNull(executable, "executable must be not null!");
 		// return type
 		final boolean isMethod = executable instanceof Method;
 		final boolean isConstructor = executable instanceof Constructor;
 		Assert.isTrue(isMethod || isConstructor, "Unsupported executable type: " + executable.getClass());
 		this.returnType = isMethod ?
-			((Method)executable).getGenericReturnType() : ((Constructor<?>)executable).getDeclaringClass();
+				((Method) executable).getGenericReturnType() : ((Constructor<?>) executable).getDeclaringClass();
 
 		// lambda info
 		this.parameterTypes = executable.getGenericParameterTypes();
@@ -42,15 +57,89 @@ public class LambdaInfo {
 		this.lambda = lambda;
 
 		// types
-		final int index = lambda.getInstantiatedMethodType().indexOf(";)");
-		this.instantiatedMethodParameterTypes = (index > -1) ? getInstantiatedMethodParamTypes(lambda, index) : EMPTY_TYPE;
+		final String instantiatedMethodType = lambda.getInstantiatedMethodType();
+		final int index = instantiatedMethodType.indexOf(";)");
+		this.instantiatedMethodParameterTypes = (index > -1) ?
+				getInstantiatedMethodParamTypes(instantiatedMethodType.substring(1, index + 1)) : EMPTY_TYPE;
+	}
+
+	/**
+	 * 实例方法参数类型
+	 *
+	 * @return 实例方法参数类型
+	 */
+	public Type[] getInstantiatedMethodParameterTypes() {
+		return instantiatedMethodParameterTypes;
+	}
+
+	/**
+	 * 获得构造或方法参数类型列表
+	 *
+	 * @return 参数类型列表
+	 */
+	public Type[] getParameterTypes() {
+		return parameterTypes;
+	}
+
+	/**
+	 * 获取返回值类型（方法引用）
+	 *
+	 * @return 返回值类型
+	 */
+	public Type getReturnType() {
+		return returnType;
+	}
+
+	/**
+	 * 方法或构造名称
+	 *
+	 * @return 方法或构造名称
+	 */
+	public String getName() {
+		return name;
+	}
+
+	/**
+	 * 字段名称，主要用于方法名称截取，方法名称必须为getXXX、isXXX、setXXX
+	 *
+	 * @return getter或setter对应的字段名称
+	 */
+	public String getFieldName() {
+		return BeanUtil.getFieldName(getName());
+	}
+
+	/**
+	 * 方法或构造对象
+	 *
+	 * @return 方法或构造对象
+	 */
+	public Executable getExecutable() {
+		return executable;
+	}
+
+	/**
+	 * 方法或构造所在类
+	 *
+	 * @return 方法或构造所在类
+	 */
+	public Class<?> getClazz() {
+		return clazz;
+	}
+
+
+	/**
+	 * 获得Lambda表达式对象
+	 *
+	 * @return 获得Lambda表达式对象
+	 */
+	public SerializedLambda getLambda() {
+		return lambda;
 	}
 
 	/**
 	 * 根据lambda对象的方法签名信息，解析获得实际的参数类型
 	 */
-	private Type[] getInstantiatedMethodParamTypes(SerializedLambda lambda, int index) {
-		final String className = lambda.getInstantiatedMethodType().substring(1, index + 1);
+	private static Type[] getInstantiatedMethodParamTypes(final String className) {
 		final String[] instantiatedTypeNames = className.split(";");
 		final Type[] types = new Type[instantiatedTypeNames.length];
 		for (int i = 0; i < instantiatedTypeNames.length; i++) {
@@ -72,32 +161,4 @@ public class LambdaInfo {
 		}
 		return types;
 	}
-
-	public Type[] getInstantiatedMethodParameterTypes() {
-		return instantiatedMethodParameterTypes;
-	}
-
-	public Type[] getParameterTypes() {
-		return parameterTypes;
-	}
-
-	public Type getReturnType() {
-		return returnType;
-	}
-
-	public String getName() {
-		return name;
-	}
-
-	public Executable getExecutable() {
-		return executable;
-	}
-
-	public Class<?> getClazz() {
-		return clazz;
-	}
-
-	public SerializedLambda getLambda() {
-		return lambda;
-	}
 }

hutool-core/src/main/java/cn/hutool/core/lang/func/LambdaUtil.java

@@ -28,27 +28,29 @@ public class LambdaUtil {
 	 * 通过对象的方法或类的静态方法引用，获取lambda实现类
 	 * 传入lambda无参数但含有返回值的情况能够匹配到此方法：
 	 * <ul>
-	 * <li>引用特定对象的实例方法：<pre>{@code
-	 * MyTeacher myTeacher = new MyTeacher();
-	 * Class<MyTeacher> supplierClass = LambdaUtil.getRealClass(myTeacher::getAge);
-	 * Assert.assertEquals(MyTeacher.class, supplierClass);
-	 * }</pre></li>
-	 * <li>引用静态无参方法：<pre>{@code
-	 * Class<MyTeacher> staticSupplierClass = LambdaUtil.getRealClass(MyTeacher::takeAge);
-	 * Assert.assertEquals(MyTeacher.class, staticSupplierClass);
-	 * }</pre></li>
+	 * 		<li>引用特定对象的实例方法：<pre>{@code
+	 * 			MyTeacher myTeacher = new MyTeacher();
+	 * 			Class<MyTeacher> supplierClass = LambdaUtil.getRealClass(myTeacher::getAge);
+	 * 			Assert.assertEquals(MyTeacher.class, supplierClass);
+	 * 			}</pre>
+	 * 		</li>
+	 * 		<li>引用静态无参方法：<pre>{@code
+	 * 			Class<MyTeacher> staticSupplierClass = LambdaUtil.getRealClass(MyTeacher::takeAge);
+	 * 			Assert.assertEquals(MyTeacher.class, staticSupplierClass);
+	 * 			}</pre>
+	 * 		</li>
 	 * </ul>
 	 * 在以下场景无法获取到正确类型
 	 * <pre>{@code
-	 * // 枚举测试，只能获取到枚举类型
-	 * Class<Enum<?>> enumSupplierClass = LambdaUtil.getRealClass(LambdaUtil.LambdaKindEnum.REF_NONE::ordinal);
-	 * Assert.assertEquals(Enum.class, enumSupplierClass);
-	 * // 调用父类方法，只能获取到父类类型
-	 * Class<Entity<?>> superSupplierClass = LambdaUtil.getRealClass(myTeacher::getId);
-	 * Assert.assertEquals(Entity.class, superSupplierClass);
-	 * // 引用父类静态带参方法，只能获取到父类类型
-	 * Class<Entity<?>> staticSuperFunctionClass = LambdaUtil.getRealClass(MyTeacher::takeId);
-	 * Assert.assertEquals(Entity.class, staticSuperFunctionClass);
+	 * 		// 枚举测试，只能获取到枚举类型
+	 * 		Class<Enum<?>> enumSupplierClass = LambdaUtil.getRealClass(LambdaUtil.LambdaKindEnum.REF_NONE::ordinal);
+	 * 		Assert.assertEquals(Enum.class, enumSupplierClass);
+	 * 		// 调用父类方法，只能获取到父类类型
+	 * 		Class<Entity<?>> superSupplierClass = LambdaUtil.getRealClass(myTeacher::getId);
+	 * 		Assert.assertEquals(Entity.class, superSupplierClass);
+	 * 		// 引用父类静态带参方法，只能获取到父类类型
+	 * 		Class<Entity<?>> staticSuperFunctionClass = LambdaUtil.getRealClass(MyTeacher::takeId);
+	 * 		Assert.assertEquals(Entity.class, staticSuperFunctionClass);
 	 * }</pre>
 	 *
 	 * @param func lambda
@@ -60,7 +62,10 @@ public class LambdaUtil {
 	@SuppressWarnings("unchecked")
 	public static <R, T extends Serializable> Class<R> getRealClass(final T func) {
 		final LambdaInfo lambdaInfo = resolve(func);
-		return (Class<R>) Opt.of(lambdaInfo).map(LambdaInfo::getInstantiatedMethodParameterTypes).filter(types -> types.length != 0).map(types -> types[types.length - 1]).orElseGet(lambdaInfo::getClazz);
+		return (Class<R>) Opt.of(lambdaInfo)
+				.map(LambdaInfo::getInstantiatedMethodParameterTypes)
+				.filter(types -> types.length != 0).map(types -> types[types.length - 1])
+				.orElseGet(lambdaInfo::getClazz);
 	}
 
 	/**

hutool-core/src/main/java/cn/hutool/core/lang/func/SerBiConsumer.java

@@ -10,6 +10,8 @@ import java.util.stream.Stream;
 /**
  * SerBiConsumer
  *
+ * @param <T> 第一个参数类型
+ * @param <U> 第二个参数类型
  * @author VampireAchao
  */
 @FunctionalInterface
@@ -24,7 +26,8 @@ public interface SerBiConsumer<T, U> extends BiConsumer<T, U>, Serializable {
 	 */
 	@SafeVarargs
 	static <T, U> SerBiConsumer<T, U> multi(final SerBiConsumer<T, U>... consumers) {
-		return Stream.of(consumers).reduce(SerBiConsumer::andThen).orElseGet(() -> (o, q) -> {});
+		return Stream.of(consumers).reduce(SerBiConsumer::andThen).orElseGet(() -> (o, q) -> {
+		});
 	}
 
 	/**
@@ -79,6 +82,7 @@ public interface SerBiConsumer<T, U> extends BiConsumer<T, U>, Serializable {
 	 * @return 什么也不做
 	 */
 	static <T, U> SerBiConsumer<T, U> nothing() {
-		return (l, r) -> {};
+		return (l, r) -> {
+		};
 	}
 }

hutool-core/src/main/java/cn/hutool/core/lang/func/SerFunction.java

@@ -30,10 +30,10 @@ public interface SerFunction<T, R> extends Function<T, R>, Serializable {
 	 * @return the function result
 	 */
 	@Override
-	default R apply(T t) {
+	default R apply(final T t) {
 		try {
 			return applying(t);
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			throw new UtilException(e);
 		}
 	}

hutool-core/src/main/java/cn/hutool/core/lang/func/SerSupplier.java

@@ -11,9 +11,10 @@ import java.util.stream.Stream;
  *
  * @author VampireAchao
  * @see Supplier
+ * @param <R> 返回值类型
  */
 @FunctionalInterface
-public interface SerSupplier<T> extends Supplier<T>, Serializable {
+public interface SerSupplier<R> extends Supplier<R>, Serializable {
 
 	/**
 	 * Gets a result.
@@ -21,7 +22,7 @@ public interface SerSupplier<T> extends Supplier<T>, Serializable {
 	 * @return a result
 	 * @throws Exception wrapped checked exceptions
 	 */
-	T getting() throws Exception;
+	R getting() throws Exception;
 
 	/**
 	 * Gets a result.
@@ -29,7 +30,7 @@ public interface SerSupplier<T> extends Supplier<T>, Serializable {
 	 * @return a result
 	 */
 	@Override
-	default T get() {
+	default R get() {
 		try {
 			return getting();
 		} catch (final Exception e) {

hutool-core/src/main/java/cn/hutool/core/map/Dict.java

@@ -7,7 +7,9 @@ import cn.hutool.core.collection.SetUtil;
 import cn.hutool.core.convert.Convert;
 import cn.hutool.core.exceptions.CloneRuntimeException;
 import cn.hutool.core.lang.Assert;
+import cn.hutool.core.lang.func.LambdaInfo;
 import cn.hutool.core.lang.func.LambdaUtil;
+import cn.hutool.core.lang.func.SerFunction;
 import cn.hutool.core.lang.func.SerSupplier;
 import cn.hutool.core.lang.getter.TypeGetter;
 
@@ -352,6 +354,19 @@ public class Dict extends CustomKeyMap<String, Object> implements TypeGetter<Str
 		return getOrDefault(key, defaultValue);
 	}
 
+	/**
+	 * 根据lambda的方法引用，获取
+	 *
+	 * @param func 方法引用
+	 * @param <P>  参数类型
+	 * @param <T>  返回值类型
+	 * @return 获取表达式对应属性和返回的对象
+	 */
+	public <P, T> T get(final SerFunction<P, T> func) {
+		final LambdaInfo lambdaInfo = LambdaUtil.resolve(func);
+		return get(lambdaInfo.getFieldName(), lambdaInfo.getReturnType());
+	}
+
 	/**
 	 * 获得特定类型值
 	 *

hutool-core/src/test/java/cn/hutool/core/lang/DictTest.java

@@ -3,14 +3,15 @@ package cn.hutool.core.lang;
 import cn.hutool.core.builder.GenericBuilder;
 import cn.hutool.core.date.DateTime;
 import cn.hutool.core.map.Dict;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
 import org.junit.Assert;
 import org.junit.Test;
 
 import java.util.HashMap;
 import java.util.Map;
 
-import static cn.hutool.core.lang.OptTest.User;
-
 public class DictTest {
 	@Test
 	public void dictTest(){
@@ -70,5 +71,16 @@ public class DictTest {
 		dict.setFields(user::getNickname, user::getUsername);
 		Assert.assertEquals("hutool", dict.get("username"));
 		Assert.assertNull(dict.get("nickname"));
+
+		// get by lambda
+		Assert.assertEquals("hutool", dict.get(User::getUsername));
+	}
+
+	@Data
+	@NoArgsConstructor
+	@AllArgsConstructor
+	static class User {
+		private String username;
+		private String nickname;
 	}
 }