com.make.json2java.Json2Java.java Source code

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Here is the source code for com.make.json2java.Json2Java.java

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/*
 * Copyright (C) 2015 Inderjeet Singh
 *
 * 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 com.make.json2java;

import java.io.IOException;
import java.io.Reader;
import java.util.Map;

import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import com.google.gson.JsonPrimitive;

/**
 * Entry class to convert a JSON file to Java source code.
 *
 * @author Inderjeet Singh
 */
public class Json2Java {
    private final ClassDefCollection classes = new ClassDefCollection();

    public void processJson(Reader reader, String pkg, String className, CustomMappings mappings)
            throws IOException {
        JsonElement root = new JsonParser().parse(reader);
        reader.close();
        processJson(pkg, className, mappings, root);
    }

    public void processJson(String source, String pkg, String className, CustomMappings mappings)
            throws IOException {
        JsonElement root = new JsonParser().parse(source);
        processJson(pkg, className, mappings, root);
    }

    private void processJson(String pkg, String className, CustomMappings mappings, JsonElement root)
            throws IOException {
        while (!(root instanceof JsonObject)) {
            if (root instanceof JsonArray) {
                for (JsonElement arrayElement : root.getAsJsonArray()) {
                    processJson(pkg, className, mappings, arrayElement);
                }
                return; // nothing much needs to be done
            } else if (root instanceof JsonPrimitive) {
                return; // can't generate classes for a primitive
            }
        }
        if (root instanceof JsonObject) {
            ClassDefCollection classes = new ClassDefCollection();
            generateClasses(classes, root.getAsJsonObject(), pkg, className);
            classes.transform(mappings);
            this.classes.merge(classes);
        }
    }

    public void transform(CustomMappings mappings) {
        classes.transform(mappings);
    }

    private void generateClasses(ClassDefCollection classes, JsonObject root, String pkg, String className)
            throws IOException {
        ClassDefinition classDef = classes.addClassDefinition(pkg, className);
        for (Map.Entry<String, JsonElement> element : root.entrySet()) {
            String name = element.getKey();
            JsonElement value = element.getValue();
            String type = Utils.lowerCaseUnderscoreToCamelCase(name, true);
            name = Utils.lowerCaseUnderscoreToCamelCase(name, false);
            if (value instanceof JsonPrimitive) {
                classDef.addField(new ClassField(name, value, type, false));
            } else if (value instanceof JsonArray) {
                classDef.addImport("java.util.List");
                classDef.addField(new ClassField(name, value, type, true));
                JsonArray array = value.getAsJsonArray();
                for (JsonElement arrayElement : array) {
                    if (arrayElement instanceof JsonObject) { // Use all elements of the array
                        generateClasses(classes, arrayElement.getAsJsonObject(), pkg, type);
                    }
                }
            }
            if (value instanceof JsonObject) {
                classDef.addField(new ClassField(name, value, type, false));
                generateClasses(classes, value.getAsJsonObject(), pkg, type);
            }
        }
    }

    public ClassDefCollection getClasses() {
        return classes;
    }

    public void addEnum(EnumDefinition enumClass) {
        this.classes.addEnumClass(enumClass);
    }
}