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Utility classes for Jetty
//
// ========================================================================
// Copyright (c) 1995 Mort Bay Consulting Pty Ltd and others.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License v. 2.0 which is available at
// https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
// ========================================================================
//
package org.eclipse.jetty.util;
import java.lang.reflect.Field;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.List;
/**
* IntrospectionUtil
*/
public class IntrospectionUtil
{
public static boolean isJavaBeanCompliantSetter(Method method)
{
if (method == null)
return false;
if (method.getReturnType() != Void.TYPE)
return false;
if (!method.getName().startsWith("set"))
return false;
if (method.getParameterCount() != 1)
return false;
return true;
}
public static Method findMethod(Class clazz, String methodName, Class[] args, boolean checkInheritance, boolean strictArgs)
throws NoSuchMethodException
{
if (clazz == null)
throw new NoSuchMethodException("No class");
if (methodName == null || methodName.trim().isEmpty())
throw new NoSuchMethodException("No method name");
Method method = null;
Method[] methods = clazz.getDeclaredMethods();
for (int i = 0; i < methods.length && method == null; i++)
{
if (methods[i].getName().equals(methodName) && checkParams(methods[i].getParameterTypes(), (args == null ? new Class[]{} : args), strictArgs))
{
method = methods[i];
}
}
if (method != null)
{
return method;
}
else if (checkInheritance)
return findInheritedMethod(clazz.getPackage(), clazz.getSuperclass(), methodName, args, strictArgs);
else
throw new NoSuchMethodException("No such method " + methodName + " on class " + clazz.getName());
}
public static Field findField(Class clazz, String targetName, Class targetType, boolean checkInheritance, boolean strictType)
throws NoSuchFieldException
{
if (clazz == null)
throw new NoSuchFieldException("No class");
if (targetName == null)
throw new NoSuchFieldException("No field name");
try
{
Field field = clazz.getDeclaredField(targetName);
if (strictType)
{
if (field.getType().equals(targetType))
return field;
}
else
{
if (field.getType().isAssignableFrom(targetType))
return field;
}
if (checkInheritance)
{
return findInheritedField(clazz.getPackage(), clazz.getSuperclass(), targetName, targetType, strictType);
}
else
throw new NoSuchFieldException("No field with name " + targetName + " in class " + clazz.getName() + " of type " + targetType);
}
catch (NoSuchFieldException e)
{
return findInheritedField(clazz.getPackage(), clazz.getSuperclass(), targetName, targetType, strictType);
}
}
public static boolean isInheritable(Package pack, Member member)
{
if (pack == null)
return false;
if (member == null)
return false;
int modifiers = member.getModifiers();
if (Modifier.isPublic(modifiers))
return true;
if (Modifier.isProtected(modifiers))
return true;
if (!Modifier.isPrivate(modifiers) && pack.equals(member.getDeclaringClass().getPackage()))
return true;
return false;
}
public static boolean checkParams(Class[] formalParams, Class[] actualParams, boolean strict)
{
if (formalParams == null)
return actualParams == null;
if (actualParams == null)
return false;
if (formalParams.length != actualParams.length)
return false;
if (formalParams.length == 0)
return true;
int j = 0;
if (strict)
{
while (j < formalParams.length && formalParams[j].equals(actualParams[j]))
{
j++;
}
}
else
{
while ((j < formalParams.length) && (formalParams[j].isAssignableFrom(actualParams[j])))
{
j++;
}
}
if (j != formalParams.length)
{
return false;
}
return true;
}
public static boolean isSameSignature(Method methodA, Method methodB)
{
if (methodA == null)
return false;
if (methodB == null)
return false;
List> parameterTypesA = Arrays.asList(methodA.getParameterTypes());
List> parameterTypesB = Arrays.asList(methodB.getParameterTypes());
if (methodA.getName().equals(methodB.getName()) &&
parameterTypesA.containsAll(parameterTypesB))
return true;
return false;
}
public static boolean isTypeCompatible(Class formalType, Class actualType, boolean strict)
{
if (formalType == null)
return actualType == null;
if (actualType == null)
return false;
if (strict)
return formalType.equals(actualType);
else
return formalType.isAssignableFrom(actualType);
}
public static boolean containsSameMethodSignature(Method method, Class c, boolean checkPackage)
{
if (checkPackage)
{
if (!c.getPackage().equals(method.getDeclaringClass().getPackage()))
return false;
}
boolean samesig = false;
Method[] methods = c.getDeclaredMethods();
for (int i = 0; i < methods.length && !samesig; i++)
{
if (IntrospectionUtil.isSameSignature(method, methods[i]))
samesig = true;
}
return samesig;
}
public static boolean containsSameFieldName(Field field, Class c, boolean checkPackage)
{
if (checkPackage)
{
if (!c.getPackage().equals(field.getDeclaringClass().getPackage()))
return false;
}
boolean sameName = false;
Field[] fields = c.getDeclaredFields();
for (int i = 0; i < fields.length && !sameName; i++)
{
if (fields[i].getName().equals(field.getName()))
sameName = true;
}
return sameName;
}
protected static Method findInheritedMethod(Package pack, Class clazz, String methodName, Class[] args, boolean strictArgs)
throws NoSuchMethodException
{
if (clazz == null)
throw new NoSuchMethodException("No class");
if (methodName == null)
throw new NoSuchMethodException("No method name");
Method method = null;
Method[] methods = clazz.getDeclaredMethods();
for (int i = 0; i < methods.length && method == null; i++)
{
if (methods[i].getName().equals(methodName) &&
isInheritable(pack, methods[i]) &&
checkParams(methods[i].getParameterTypes(), args, strictArgs))
method = methods[i];
}
if (method != null)
{
return method;
}
else
return findInheritedMethod(clazz.getPackage(), clazz.getSuperclass(), methodName, args, strictArgs);
}
protected static Field findInheritedField(Package pack, Class clazz, String fieldName, Class fieldType, boolean strictType)
throws NoSuchFieldException
{
if (clazz == null)
throw new NoSuchFieldException("No class");
if (fieldName == null)
throw new NoSuchFieldException("No field name");
try
{
Field field = clazz.getDeclaredField(fieldName);
if (isInheritable(pack, field) && isTypeCompatible(fieldType, field.getType(), strictType))
return field;
else
return findInheritedField(clazz.getPackage(), clazz.getSuperclass(), fieldName, fieldType, strictType);
}
catch (NoSuchFieldException e)
{
return findInheritedField(clazz.getPackage(), clazz.getSuperclass(), fieldName, fieldType, strictType);
}
}
}