io.atlasmap.java.core.ClassHelper Maven / Gradle / Ivy

Go to download
/**
 * Copyright (C) 2017 Red Hat, Inc.
 * 
 * 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
 * 

 * http://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 io.atlasmap.java.core;

import java.lang.reflect.Array;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import io.atlasmap.api.AtlasException;
import io.atlasmap.core.AtlasPath;
import io.atlasmap.core.AtlasPath.SegmentContext;
import io.atlasmap.core.AtlasUtil;
import io.atlasmap.spi.AtlasInternalSession;
import io.atlasmap.v2.AuditStatus;
import io.atlasmap.v2.CollectionType;

public class ClassHelper {

    public static List getterMethodNames(String fieldName) {
        List opts = new ArrayList();
        opts.add(getMethodNameFromFieldName(fieldName));
        opts.add(isMethodNameFromFieldName(fieldName));
        return opts;
    }

    public static String getMethodNameFromFieldName(String fieldName) {
        return "get" + StringUtil.capitalizeFirstLetter(fieldName);
    }

    public static String isMethodNameFromFieldName(String fieldName) {
        return "is" + StringUtil.capitalizeFirstLetter(fieldName);
    }

    public static Method detectGetterMethod(Class clazz, String methodName) throws NoSuchMethodException {

        Method[] methods = clazz.getMethods();

        for (Method method : methods) {
            if (method.getName().equals(methodName) && method.getParameterCount() == 0) {
                return method;
            }
        }

        throw new NoSuchMethodException(
                String.format("No matching getter method for class=%s method=%s", clazz.getName(), methodName));
    }

    public static Method detectSetterMethod(Class clazz, String methodName, Class paramType)
            throws NoSuchMethodException {
        List candidates = new ArrayList();

        Method[] methods = clazz.getMethods();
        for (Method method : methods) {
            if (method.getName().equals(methodName) && method.getParameterCount() == 1) {
                candidates.add(method);
            }
        }

        String paramTypeClassName = paramType == null ? null : paramType.getName();

        if (candidates.size() == 0) {
            throw new NoSuchMethodException(
                    String.format("No matching setter found for class=%s method=%s paramType=%s", clazz.getName(),
                            methodName, paramTypeClassName));
        }

        if (paramType != null) {
            for (Method candidate : candidates) {
                // Getter and setter w/ same returnType & paramType
                if (candidate.getParameterTypes()[0].isAssignableFrom(paramType)) {
                    return candidate;
                }
            }
            throw new NoSuchMethodException(
                    String.format("No matching setter found for class=%s method=%s paramType=%s", clazz.getName(),
                            methodName, paramTypeClassName));
        }

        // paramType is null, let's do some more digging...

        if (candidates.size() == 1) {
            return candidates.get(0);
        }

        Method getter = null;
        Class returnType = null;
        for (String prefix : Arrays.asList("get", "is")) {
            try {
                getter = detectGetterMethod(clazz, methodName.replace("set", prefix));
                returnType = getter.getReturnType();
                break;
            } catch (NoSuchMethodException nsme) {
                // System.out.println("\t\t could not find getter " + methodName.replace("set",
                // prefix));
            }
        }

        // Solid match
        for (Method candidate : candidates) {
            // Getter and setter w/ same returnType & paramType
            Class candidateReturnType = candidate.getParameterTypes()[0];
            if (returnType == null) {
                if (candidateReturnType == null) {
                    return candidate;
                }
            } else if (returnType.isAssignableFrom(candidateReturnType)) {
                return candidate;
            }
        }

        // Not as good of a match .. find one with a matching converter
        /*
         * for (Method candidate : candidates) {
         * if(candidate.getParameterTypes()[0].equals(String.class)) { return candidate;
         * } }
         */

        // Yikes! User should specify type, or provide a converter
        throw new NoSuchMethodException(String.format("Unable to auto-detect setter class=%s method=%s paramType=%s",
                clazz.getName(), methodName, paramTypeClassName));
    }

    public static List