com.google.javascript.jscomp.transpile.TranspilerBuilder Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of closure-compiler-unshaded Show documentation

Closure Compiler is a JavaScript optimizing compiler. It parses your JavaScript, analyzes it, removes dead code and rewrites and minimizes what's left. It also checks syntax, variable references, and types, and warns about common JavaScript pitfalls. It is used in many of Google's JavaScript apps, including Gmail, Google Web Search, Google Maps, and Google Docs.

The newest version!

/*
 * Copyright 2016 The Closure Compiler Authors.
 *
 * 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.javascript.jscomp.transpile;

import com.google.common.cache.CacheBuilder;
import com.google.errorprone.annotations.CheckReturnValue;

/**
 * Basic Transpiler implementation for outputting ES5 code.
 */
public final class TranspilerBuilder {

  /**
   * Returns a new TranspilerBuilder that transpiles down to ES5.
   */
  public static TranspilerBuilder toEs5() {
    return TO_ES5;
  }

  private static final TranspilerBuilder TO_ES5 =
      new TranspilerBuilder(
          new BaseTranspiler(new BaseTranspiler.CompilerSupplier(), "es6_runtime"));

  private final Transpiler transpiler;

  TranspilerBuilder(Transpiler transpiler) {
    this.transpiler = transpiler;
  }

  /**
   * Returns a TranspilerBuilder with cached transpilations, using the default
   * cache settings (maximum size of 10,000).  Note that the builder itself is
   * not changed.
   */
  @CheckReturnValue
  public TranspilerBuilder caching() {
    return caching(DEFAULT_CACHE_SPEC);
  }

  /**
   * Returns a TranspilerBuilder with cached transpilations, using the given cache spec. Note that
   * the builder itself is not changed.
   */
  @CheckReturnValue
  public TranspilerBuilder caching(String spec) {
    return caching(CacheBuilder.from(spec));
  }

  /**
   * Returns a TranspilerBuilder with cached transpilations, using the given cache builder. Note
   * that the builder itself is not changed.
   */
  @CheckReturnValue
  public TranspilerBuilder caching(CacheBuilder builder) {
    return new TranspilerBuilder(new CachingTranspiler(transpiler, builder));
  }

  private static final String DEFAULT_CACHE_SPEC = "maximumSize=10000";

  /**
   * Returns the built Transpiler.
   */
  public Transpiler build() {
    return transpiler;
  }
}