com.google.devtools.j2objc.gen.ObjectiveCSegmentedHeaderGenerator.java Source code

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Here is the source code for com.google.devtools.j2objc.gen.ObjectiveCSegmentedHeaderGenerator.java

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/*
 * 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.google.devtools.j2objc.gen;

import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
import com.google.devtools.j2objc.types.Import;

import java.util.Collection;
import java.util.List;
import java.util.Set;

/**
 * Generates segmented Objective-C header files from compilation units. In a
 * segmented header each type is given separate header guards and can be
 * included without including the other types in the file.
 *
 * @author Keith Stanger
 */
public class ObjectiveCSegmentedHeaderGenerator extends ObjectiveCHeaderGenerator {

    protected ObjectiveCSegmentedHeaderGenerator(GenerationUnit unit) {
        super(unit);
    }

    public static void generate(GenerationUnit unit) {
        new ObjectiveCSegmentedHeaderGenerator(unit).generate();
    }

    @Override
    protected void generateFileHeader() {
        println("#include \"J2ObjC_header.h\"");
        newline();
        printf("#pragma push_macro(\"INCLUDE_ALL_%s\")\n", varPrefix);
        printf("#ifdef RESTRICT_%s\n", varPrefix);
        printf("#define INCLUDE_ALL_%s 0\n", varPrefix);
        println("#else");
        printf("#define INCLUDE_ALL_%s 1\n", varPrefix);
        println("#endif");
        printf("#undef RESTRICT_%s\n", varPrefix);

        for (GeneratedType type : Lists.reverse(getOrderedTypes())) {
            printLocalIncludes(type);
        }
        pushIgnoreDeprecatedDeclarationsPragma();

        // Print OCNI blocks
        Collection<String> nativeBlocks = getGenerationUnit().getNativeHeaderBlocks();
        if (!nativeBlocks.isEmpty()) {
            // Use a normal header guard for OCNI code outside of a type declaration.
            printf("\n#ifndef %s_H\n", varPrefix);
            printf("#define %s_H\n", varPrefix);
            for (String code : nativeBlocks) {
                print(code);
            }
            printf("\n#endif // %s_H\n", varPrefix);
        }
    }

    /**
     * Given a {@link com.google.devtools.j2objc.gen.GeneratedType}
     * and its collected {@link com.google.devtools.j2objc.types.Import}s,
     * print its 'local includes'; viz.,
     * {@code INCLUDE} directives for all supertypes that are defined in the
     * current segmented header.
     */
    private void printLocalIncludes(GeneratedType type) {
        String typeName = type.getTypeName();
        Set<Import> includes = type.getHeaderIncludes();
        List<Import> localImports = Lists.newArrayList();
        for (Import imp : includes) {
            if (isLocalType(imp.getTypeName())) {
                localImports.add(imp);
            }
        }
        if (!localImports.isEmpty()) {
            printf("#ifdef INCLUDE_%s\n", typeName);
            for (Import imp : localImports) {
                printf("#define INCLUDE_%s 1\n", imp.getTypeName());
            }
            println("#endif");
        }
    }

    @Override
    protected void generateFileFooter() {
        // Don't need #endif for file-level header guard.
        newline();
        popIgnoreDeprecatedDeclarationsPragma();
        printf("#pragma pop_macro(\"INCLUDE_ALL_%s\")\n", varPrefix);
    }

    @Override
    protected void printTypeDeclaration(GeneratedType type) {
        String typeName = type.getTypeName();
        String code = type.getPublicDeclarationCode();
        if (code.length() == 0) {
            return;
        }

        newline();
        printf("#if !defined (%s_) && (INCLUDE_ALL_%s || defined(INCLUDE_%s))\n", typeName, varPrefix, typeName);
        printf("#define %s_\n", typeName);

        Set<Import> forwardDeclarations = Sets.newHashSet(type.getHeaderForwardDeclarations());

        for (Import imp : type.getHeaderIncludes()) {
            // Verify this import isn't declared in this source file.
            if (isLocalType(imp.getTypeName())) {
                continue;
            }
            newline();
            printf("#define RESTRICT_%s 1\n", getVarPrefix(imp.getImportFileName()));
            printf("#define INCLUDE_%s 1\n", imp.getTypeName());
            printf("#include \"%s\"\n", imp.getImportFileName());
            forwardDeclarations.remove(imp);
        }

        printForwardDeclarations(forwardDeclarations);

        print(code);
        newline();
        println("#endif");
    }
}