SwiftDocumentContext.java

/*
 * Copyright (C) 2012 Facebook, 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 com.facebook.swift.generator;

import com.facebook.swift.generator.template.TemplateContextGenerator;
import com.facebook.swift.parser.ThriftIdlParser;
import com.facebook.swift.parser.model.Document;
import com.google.common.base.Charsets;
import com.google.common.base.Preconditions;
import com.google.common.io.Resources;

import java.io.IOException;
import java.net.URI;

public class SwiftDocumentContext
{
    public static final String JAVA_SWIFT_NAMESPACE = "java.swift";
    public static final String PLAIN_JAVA_NAMESPACE = "java";
    private final Document document;
    private final String namespace;
    private final SwiftGeneratorConfig generatorConfig;
    private final TypeRegistry typeRegistry;
    private final TypedefRegistry typedefRegistry;
    private final TypeToJavaConverter typeConverter;
    private final ConstantRenderer constantRenderer;
    private final URI thriftIdlUri;

    public SwiftDocumentContext(final URI thriftIdlUri,
                                final String namespace,
                                final SwiftGeneratorConfig generatorConfig,
                                final TypeRegistry typeRegistry,
                                final TypedefRegistry typedefRegistry) throws IOException
    {
        this.document = ThriftIdlParser.parseThriftIdl(Resources.asCharSource(thriftIdlUri.toURL(), Charsets.UTF_8));
        this.thriftIdlUri = thriftIdlUri;
        this.namespace = namespace;
        this.generatorConfig = generatorConfig;
        this.typeRegistry = typeRegistry;
        this.typedefRegistry = typedefRegistry;
        this.typeConverter = new TypeToJavaConverter(typeRegistry,
                                                     typedefRegistry,
                                                     namespace,
                                                     getJavaPackage());
        this.constantRenderer = new ConstantRenderer(typeConverter, namespace, typeRegistry, typedefRegistry);
    }

    public String getNamespace()
    {
        return namespace;
    }

    public Document getDocument()
    {
        return document;
    }

    public TypeRegistry getTypeRegistry()
    {
        return typeRegistry;
    }

    public TypedefRegistry getTypedefRegistry()
    {
        return typedefRegistry;
    }

    public TypeToJavaConverter getTypeConverter()
    {
        return typeConverter;
    }

    public ConstantRenderer getConstantRenderer()
    {
        return constantRenderer;
    }

    public TemplateContextGenerator getTemplateContextGenerator()
    {
        return new TemplateContextGenerator(this, generatorConfig, typeRegistry, typeConverter, constantRenderer, namespace);
    }

    public String getJavaPackage()
    {
        String effectiveJavaNamespace = JAVA_SWIFT_NAMESPACE;
        if (generatorConfig.containsTweak(SwiftGeneratorTweak.USE_PLAIN_JAVA_NAMESPACE)) {
            effectiveJavaNamespace = PLAIN_JAVA_NAMESPACE;
        }

        // Override takes precedence
        String javaPackage = generatorConfig.getOverridePackage();
        // Otherwise fallback on package specified in .thrift file
        if (javaPackage == null) {
            javaPackage = getDocument().getHeader().getNamespace(effectiveJavaNamespace);
        }
        // Try to fallback to plain Java namespace if java.swift is not present in IDL
        if (javaPackage == null &&
            generatorConfig.containsTweak(SwiftGeneratorTweak.FALLBACK_TO_PLAIN_JAVA_NAMESPACE)) {
            javaPackage = getDocument().getHeader().getNamespace(PLAIN_JAVA_NAMESPACE);
        }

        // Or the default if we don't have an override package or a package in the .thrift file
        if (javaPackage == null) {
            javaPackage = generatorConfig.getDefaultPackage();
        }

        // If none of the above options get us a package to use, fail
        Preconditions.checkState(javaPackage != null, "thrift uri %s does not declare a '%s' namespace!",
            getThriftIdlUri(), effectiveJavaNamespace);

        return javaPackage;
    }

    public URI getThriftIdlUri() {
        return thriftIdlUri;
    }

    public SwiftGeneratorConfig getSwiftGeneratorConfig() {
        return generatorConfig;
    }
}