ReflectorTest.java

/*
 *    Copyright 2009-2025 the original author or authors.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *       https://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */
package org.apache.ibatis.reflection;

import static com.googlecode.catchexception.apis.BDDCatchException.caughtException;
import static com.googlecode.catchexception.apis.BDDCatchException.when;
import static org.assertj.core.api.BDDAssertions.then;
import static org.junit.jupiter.api.Assertions.assertArrayEquals;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.List;
import java.util.Map.Entry;

import org.apache.ibatis.reflection.invoker.Invoker;
import org.apache.ibatis.type.TypeReference;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

class ReflectorTest {

  @Test
  void getSetterType() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Section.class);
    Assertions.assertEquals(Long.class, reflector.getSetterType("id"));
  }

  @Test
  void getGetterType() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Section.class);
    Assertions.assertEquals(Long.class, reflector.getGetterType("id"));
  }

  @Test
  void shouldNotGetClass() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Section.class);
    Assertions.assertFalse(reflector.hasGetter("class"));
  }

  @Test
  void shouldGetGenericGetterType() {
    Type type = new TypeReference<Entity<List<String>>>() {
    }.getRawType();
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(type);
    Assertions.assertTrue(reflector.hasGetter("id"));
    Assertions.assertEquals(List.class, reflector.getGetterType("id"));
    Entry<Type, Class<?>> entry = reflector.getGenericGetterType("id");
    Assertions.assertEquals(List.class, entry.getValue());
    Assertions.assertTrue(entry.getKey() instanceof ParameterizedType);
    ParameterizedType parameterizedType = (ParameterizedType) entry.getKey();
    Assertions.assertEquals(List.class, parameterizedType.getRawType());
    Assertions.assertEquals(String.class, parameterizedType.getActualTypeArguments()[0]);
  }

  interface Entity<T> {
    T getId();

    void setId(T id);
  }

  abstract static class AbstractEntity implements Entity<Long> {

    private Long id;

    @Override
    public Long getId() {
      return id;
    }

    @Override
    public void setId(Long id) {
      this.id = id;
    }
  }

  static class Section extends AbstractEntity implements Entity<Long> {
  }

  @Test
  void shouldResolveSetterParam() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    assertEquals(String.class, reflector.getSetterType("id"));
  }

  @Test
  void shouldResolveParameterizedSetterParam() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    assertEquals(List.class, reflector.getSetterType("list"));
  }

  @Test
  void shouldResolveArraySetterParam() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    Class<?> clazz = reflector.getSetterType("array");
    assertTrue(clazz.isArray());
    assertEquals(String.class, clazz.getComponentType());
  }

  @Test
  void shouldResolveGetterType() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    assertEquals(String.class, reflector.getGetterType("id"));
  }

  @Test
  void shouldResolveSetterTypeFromPrivateField() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    assertEquals(String.class, reflector.getSetterType("fld"));
  }

  @Test
  void shouldResolveGetterTypeFromPublicField() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    assertEquals(String.class, reflector.getGetterType("pubFld"));
  }

  @Test
  void shouldResolveParameterizedGetterType() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    assertEquals(List.class, reflector.getGetterType("list"));
  }

  @Test
  void shouldResolveArrayGetterType() {
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Child.class);
    Class<?> clazz = reflector.getGetterType("array");
    assertTrue(clazz.isArray());
    assertEquals(String.class, clazz.getComponentType());
  }

  abstract static class Parent<T extends Serializable> {
    protected T id;
    protected List<T> list;
    protected T[] array;
    private T fld;
    public T pubFld;

    public T getId() {
      return id;
    }

    public void setId(T id) {
      this.id = id;
    }

    public List<T> getList() {
      return list;
    }

    public void setList(List<T> list) {
      this.list = list;
    }

    public T[] getArray() {
      return array;
    }

    public void setArray(T[] array) {
      this.array = array;
    }

    public T getFld() {
      return fld;
    }
  }

  static class Child extends Parent<String> {
  }

  @Test
  void shouldResolveReadonlySetterWithOverload() {
    class BeanClass implements BeanInterface<String> {
      @Override
      public void setId(String id) {
        // Do nothing
      }
    }
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(BeanClass.class);
    assertEquals(String.class, reflector.getSetterType("id"));
  }

  interface BeanInterface<T> {
    void setId(T id);
  }

  @Test
  void shouldSettersWithUnrelatedArgTypesThrowException() throws Exception {
    @SuppressWarnings("unused")
    class BeanClass {
      public void setProp1(String arg) {
      }

      public void setProp2(String arg) {
      }

      public void setProp2(Integer arg) {
      }

      public void setProp2(boolean arg) {
      }
    }
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(BeanClass.class);

    List<String> setableProps = Arrays.asList(reflector.getSetablePropertyNames());
    assertTrue(setableProps.contains("prop1"));
    assertTrue(setableProps.contains("prop2"));
    assertEquals("prop1", reflector.findPropertyName("PROP1"));
    assertEquals("prop2", reflector.findPropertyName("PROP2"));

    assertEquals(String.class, reflector.getSetterType("prop1"));
    assertNotNull(reflector.getSetInvoker("prop1"));

    Class<?> paramType = reflector.getSetterType("prop2");
    assertTrue(String.class.equals(paramType) || Integer.class.equals(paramType) || boolean.class.equals(paramType));

    Invoker ambiguousInvoker = reflector.getSetInvoker("prop2");
    Object[] param = String.class.equals(paramType) ? new String[] { "x" } : new Integer[] { 1 };
    when(() -> ambiguousInvoker.invoke(new BeanClass(), param));
    then(caughtException()).isInstanceOf(ReflectionException.class)
        .hasMessageMatching("Ambiguous setters defined for property 'prop2' in class '"
            + BeanClass.class.getName().replace("$", "\\$")
            + "' with types '(java.lang.String|java.lang.Integer|boolean)' and '(java.lang.String|java.lang.Integer|boolean)'\\.");
  }

  @Test
  void shouldTwoGettersForNonBooleanPropertyThrowException() throws Exception {
    @SuppressWarnings("unused")
    class BeanClass {
      public Integer getProp1() {
        return 1;
      }

      public int getProp2() {
        return 0;
      }

      public int isProp2() {
        return 0;
      }
    }
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(BeanClass.class);

    List<String> getableProps = Arrays.asList(reflector.getGetablePropertyNames());
    assertTrue(getableProps.contains("prop1"));
    assertTrue(getableProps.contains("prop2"));
    assertEquals("prop1", reflector.findPropertyName("PROP1"));
    assertEquals("prop2", reflector.findPropertyName("PROP2"));

    assertEquals(Integer.class, reflector.getGetterType("prop1"));
    Invoker getInvoker = reflector.getGetInvoker("prop1");
    assertEquals(Integer.valueOf(1), getInvoker.invoke(new BeanClass(), null));

    Class<?> paramType = reflector.getGetterType("prop2");
    assertEquals(int.class, paramType);

    Invoker ambiguousInvoker = reflector.getGetInvoker("prop2");
    when(() -> ambiguousInvoker.invoke(new BeanClass(), new Integer[] { 1 }));
    then(caughtException()).isInstanceOf(ReflectionException.class)
        .hasMessageContaining("Illegal overloaded getter method with ambiguous type for property 'prop2' in class '"
            + BeanClass.class.getName()
            + "'. This breaks the JavaBeans specification and can cause unpredictable results.");
  }

  @Test
  void shouldTwoGettersWithDifferentTypesThrowException() throws Exception {
    @SuppressWarnings("unused")
    class BeanClass {
      public Integer getProp1() {
        return 1;
      }

      public Integer getProp2() {
        return 1;
      }

      public boolean isProp2() {
        return false;
      }
    }
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(BeanClass.class);

    List<String> getableProps = Arrays.asList(reflector.getGetablePropertyNames());
    assertTrue(getableProps.contains("prop1"));
    assertTrue(getableProps.contains("prop2"));
    assertEquals("prop1", reflector.findPropertyName("PROP1"));
    assertEquals("prop2", reflector.findPropertyName("PROP2"));

    assertEquals(Integer.class, reflector.getGetterType("prop1"));
    Invoker getInvoker = reflector.getGetInvoker("prop1");
    assertEquals(Integer.valueOf(1), getInvoker.invoke(new BeanClass(), null));

    Class<?> returnType = reflector.getGetterType("prop2");
    assertTrue(Integer.class.equals(returnType) || boolean.class.equals(returnType));

    Invoker ambiguousInvoker = reflector.getGetInvoker("prop2");
    when(() -> ambiguousInvoker.invoke(new BeanClass(), null));
    then(caughtException()).isInstanceOf(ReflectionException.class)
        .hasMessageContaining("Illegal overloaded getter method with ambiguous type for property 'prop2' in class '"
            + BeanClass.class.getName()
            + "'. This breaks the JavaBeans specification and can cause unpredictable results.");
  }

  @Test
  void shouldAllowTwoBooleanGetters() throws Exception {
    @SuppressWarnings("unused")
    class Bean {
      // JavaBean Spec allows this (see #906)
      public boolean isBool() {
        return true;
      }

      public boolean getBool() {
        return false;
      }

      public void setBool(boolean bool) {
      }
    }
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Bean.class);
    assertTrue((Boolean) reflector.getGetInvoker("bool").invoke(new Bean(), new Byte[0]));
  }

  @Test
  void shouldIgnoreBestMatchSetterIfGetterIsAmbiguous() throws Exception {
    @SuppressWarnings("unused")
    class Bean {
      public Integer isBool() {
        return Integer.valueOf(1);
      }

      public Integer getBool() {
        return Integer.valueOf(2);
      }

      public void setBool(boolean bool) {
      }

      public void setBool(Integer bool) {
      }
    }
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Bean.class);
    Class<?> paramType = reflector.getSetterType("bool");
    Object[] param = boolean.class.equals(paramType) ? new Boolean[] { true } : new Integer[] { 1 };
    Invoker ambiguousInvoker = reflector.getSetInvoker("bool");
    when(() -> ambiguousInvoker.invoke(new Bean(), param));
    then(caughtException()).isInstanceOf(ReflectionException.class).hasMessageMatching(
        "Ambiguous setters defined for property 'bool' in class '" + Bean.class.getName().replace("$", "\\$")
            + "' with types '(java.lang.Integer|boolean)' and '(java.lang.Integer|boolean)'\\.");
  }

  @Test
  void shouldGetGenericGetter() throws Exception {
    class Foo<T> {
    }
    @SuppressWarnings("unused")
    class Bean {
      public void setFoo(Foo<String> foo) {
      }

      public Foo<String> getFoo() {
        return null;
      }
    }
    ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
    Reflector reflector = reflectorFactory.findForClass(Bean.class);
    ParameterizedType getter = (ParameterizedType) reflector.getGenericGetterType("foo").getKey();
    assertEquals(Foo.class, getter.getRawType());
    assertArrayEquals(new Type[] { String.class }, getter.getActualTypeArguments());
    ParameterizedType setter = (ParameterizedType) reflector.getGenericSetterType("foo").getKey();
    assertEquals(Foo.class, setter.getRawType());
    assertArrayEquals(new Type[] { String.class }, setter.getActualTypeArguments());
  }
}