me.j360.dubbo.modules.util.reflect.ReflectionUtil.java Source code

Introduction

Here is the source code for me.j360.dubbo.modules.util.reflect.ReflectionUtil.java

Source

/*******************************************************************************
 * Copyright (c) 2005, 2014 springside.github.io
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 *******************************************************************************/
package me.j360.dubbo.modules.util.reflect;

import me.j360.dubbo.modules.util.base.ExceptionUtil;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.ClassUtils;
import org.apache.commons.lang3.reflect.ConstructorUtils;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
 * ??.
 * 
 * ???modifier????CheckedUnChecked
 * 
 * 1. ??
 * 
 * 2. ??? MethodInvoker ? FastMethodInvoker.
 * 
 * 3. ??Field?????.
 */
@SuppressWarnings("unchecked")
public class ReflectionUtil {

    ///////////  ///////////
    /**
     * Getter, private/protected.
     */
    public static <T> T invokeGetter(Object obj, String propertyName) {
        Method method = ClassUtil.getGetterMethod(obj.getClass(), propertyName);
        if (method == null) {
            throw new IllegalArgumentException(
                    "Could not find getter method [" + propertyName + "] on target [" + obj + ']');
        }
        return (T) invokeMethod(obj, method);
    }

    /**
     * Setter, private/protected, value?.
     */
    public static void invokeSetter(Object obj, String propertyName, Object value) {
        Method method = ClassUtil.getSetterMethod(obj.getClass(), propertyName, value.getClass());
        if (method == null) {
            throw new IllegalArgumentException(
                    "Could not find getter method [" + propertyName + "] on target [" + obj + ']');
        }
        invokeMethod(obj, method, value);
    }

    /**
     * ?, private/protected, ??getter.
     */
    public static <T> T getFieldValue(final Object obj, final String fieldName) {
        Field field = ClassUtil.getAccessibleField(obj.getClass(), fieldName);
        if (field == null) {
            throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + ']');
        }
        return getFieldValue(obj, field);
    }

    /**
     * ?Field, ?, ??getter.
     */
    public static <T> T getFieldValue(final Object obj, final Field field) {
        try {
            return (T) field.get(obj);
        } catch (Exception e) {
            throw convertReflectionExceptionToUnchecked(e);
        }
    }

    /**
     * , private/protected, ??setter.
     */
    public static void setFieldValue(final Object obj, final String fieldName, final Object value) {
        Field field = ClassUtil.getAccessibleField(obj.getClass(), fieldName);
        if (field == null) {
            throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + ']');
        }
        setField(obj, field, value);
    }

    /**
     * ?Field, ?, ??setter.
     */
    public static void setField(final Object obj, Field field, final Object value) {
        try {
            field.set(obj, value);
        } catch (Exception e) {
            throw convertReflectionExceptionToUnchecked(e);
        }
    }

    /**
     * ?Getter?, ????.
     */
    public static <T> T getProperty(Object obj, String propertyName) {
        Method method = ClassUtil.getGetterMethod(obj.getClass(), propertyName);
        if (method != null) {
            try {
                return (T) method.invoke(obj, ArrayUtils.EMPTY_OBJECT_ARRAY);
            } catch (Exception e) {
                throw convertReflectionExceptionToUnchecked(e);
            }
        } else {
            return (T) getFieldValue(obj, propertyName);
        }
    }

    /**
     * ?Setter, ???, value?.
     */
    public static void setProperty(Object obj, String propertyName, final Object value) {
        Method method = ClassUtil.getSetterMethod(obj.getClass(), propertyName, value.getClass());
        if (method != null) {
            try {
                method.invoke(obj, value);
            } catch (Exception e) {
                throw convertReflectionExceptionToUnchecked(e);
            }
        } else {
            setFieldValue(obj, propertyName, value);
        }
    }

    ///////////  ////////////
    /**
     * , private/protected.
     * 
     * ???
     */
    public static <T> T invokeMethod(Object obj, String methodName, Object... args) {
        Object[] theArgs = ArrayUtils.nullToEmpty(args);
        final Class<?>[] parameterTypes = ClassUtils.toClass(theArgs);
        return (T) invokeMethod(obj, methodName, theArgs, parameterTypes);
    }

    /**
     * , private/protected.
     * 
     * ???
     */
    public static <T> T invokeMethod(final Object obj, final String methodName, final Object[] args,
            final Class<?>[] parameterTypes) {
        Method method = ClassUtil.getAccessibleMethod(obj.getClass(), methodName, parameterTypes);
        if (method == null) {
            throw new IllegalArgumentException(
                    "Could not find method [" + methodName + "] on target [" + obj + ']');
        }
        return invokeMethod(obj, method, args);
    }

    /**
     * , private/protected
     * 
     * ???????. ????, ??
     */
    public static <T> T invokeMethodByName(final Object obj, final String methodName, final Object[] args) {
        Method method = ClassUtil.getAccessibleMethodByName(obj.getClass(), methodName);
        if (method == null) {
            throw new IllegalArgumentException(
                    "Could not find method [" + methodName + "] on target [" + obj + ']');
        }
        return invokeMethod(obj, method, args);
    }

    /**
     * Method
     */
    public static <T> T invokeMethod(final Object obj, Method method, Object... args) {
        try {
            return (T) method.invoke(obj, args);
        } catch (Exception e) {
            throw ExceptionUtil.uncheckedAndWrap(e);
        }
    }

    //////////  ////////
    /**
     * .
     */
    public static <T> T invokeConstructor(final Class<T> cls, Object... args) {
        try {
            return ConstructorUtils.invokeConstructor(cls, args);
        } catch (Exception e) {
            throw ExceptionUtil.uncheckedAndWrap(e);
        }
    }

    ///////  ////////

    /**
     * ??checked exception?unchecked exception.
     */
    public static RuntimeException convertReflectionExceptionToUnchecked(Exception e) {
        if ((e instanceof IllegalAccessException) || (e instanceof NoSuchMethodException)) {
            return new IllegalArgumentException(e);
        } else if (e instanceof InvocationTargetException) {
            return new RuntimeException(((InvocationTargetException) e).getTargetException());
        } else if (e instanceof RuntimeException) {
            return (RuntimeException) e;
        }
        return new ExceptionUtil.UncheckedException(e);
    }
}