Java tutorial
/* * Copyright 2009 Google 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.google.template.soy.shared.internal; import com.google.common.base.CaseFormat; import com.google.common.collect.ImmutableMap; import com.google.common.collect.ImmutableSet; import com.google.template.soy.shared.restricted.SoyFunction; import java.util.Map; import java.util.Set; /** * Enum of built-in functions supported in Soy expressions. * * <p> Important: Do not use outside of Soy code (treat as superpackage-private). * */ public enum BuiltinFunction implements SoyFunction { IS_FIRST, IS_LAST, INDEX, QUOTE_KEYS_IF_JS, CHECK_NOT_NULL; /** Map of NonpluginFunctions by function name. */ private static final Map<String, BuiltinFunction> NONPLUGIN_FUNCTIONS_BY_NAME; static { ImmutableMap.Builder<String, BuiltinFunction> mapBuilder = ImmutableMap.builder(); for (BuiltinFunction nonpluginFn : values()) { mapBuilder.put(nonpluginFn.functionName, nonpluginFn); } NONPLUGIN_FUNCTIONS_BY_NAME = mapBuilder.build(); } /** * Returns the NonpluginFunction for the given function name, or null if not found. * @param functionName The function name to retrieve. */ public static BuiltinFunction forFunctionName(String functionName) { return NONPLUGIN_FUNCTIONS_BY_NAME.get(functionName); } /** The function name. */ private final String functionName; BuiltinFunction() { this.functionName = CaseFormat.UPPER_UNDERSCORE.to(CaseFormat.LOWER_CAMEL, name()); } @Override public String getName() { return functionName; } @Override public Set<Integer> getValidArgsSizes() { return ImmutableSet.of(1); // All built-in functions are unary. } }