Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 org.apache.james.rrt.lib; import java.io.Serializable; import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; import java.util.StringTokenizer; import org.apache.james.rrt.lib.Mapping.Type; import com.google.common.base.Function; import com.google.common.base.Joiner; import com.google.common.base.MoreObjects; import com.google.common.base.Objects; import com.google.common.base.Optional; import com.google.common.base.Preconditions; import com.google.common.base.Predicate; import com.google.common.base.Predicates; import com.google.common.collect.FluentIterable; import com.google.common.collect.ImmutableList; import com.google.common.collect.Iterables; import com.google.common.collect.Lists; public class MappingsImpl implements Mappings, Serializable { private static final long serialVersionUID = 1L; public static MappingsImpl empty() { return builder().build(); } public static MappingsImpl fromRawString(String raw) { return fromCollection(mappingToCollection(raw)); } private static ArrayList<String> mappingToCollection(String rawMapping) { ArrayList<String> map = new ArrayList<String>(); StringTokenizer tokenizer = new StringTokenizer(rawMapping, RecipientRewriteTableUtil.getSeparator(rawMapping)); while (tokenizer.hasMoreTokens()) { final String raw = tokenizer.nextToken().trim(); map.add(raw); } return map; } public static MappingsImpl fromCollection(Collection<String> mappings) { Builder builder = builder(); for (String mapping : mappings) { builder.add(mapping); } return builder.build(); } public static MappingsImpl fromMappings(Iterable<Mapping> mappings) { Builder builder = builder(); for (Mapping mapping : mappings) { builder.add(mapping); } return builder.build(); } public static Builder from(Mappings from) { Builder builder = new Builder(); builder.addAll(from); return builder; } public static Builder builder() { return new Builder(); } public static class Builder { private final ImmutableList.Builder<Mapping> mappings; private Builder() { mappings = ImmutableList.builder(); } public Builder add(String mapping) { return add(MappingImpl.of(mapping)); } public Builder add(Mapping mapping) { mappings.add(mapping); return this; } public Builder addAll(Mappings mappings) { this.mappings.addAll(mappings); return this; } public MappingsImpl build() { return new MappingsImpl(mappings.build()); } } private final ImmutableList<Mapping> mappings; private MappingsImpl(Collection<Mapping> mappings) { this.mappings = ImmutableList.copyOf(mappings); } @Override public Iterable<String> asStrings() { return FluentIterable.from(mappings).transform(new Function<Mapping, String>() { @Override public String apply(Mapping input) { return input.asString(); } }); } @Override public boolean contains(String mapping) { return mappings.contains(mapping); } @Override public int size() { return mappings.size(); } @Override public Mappings remove(String mappingAsString) { MappingImpl mapping = MappingImpl.of(mappingAsString); if (mappings.contains(mapping)) { ArrayList<Mapping> updatedMappings = Lists.newArrayList(mappings); updatedMappings.remove(mapping); return new MappingsImpl(updatedMappings); } return this; } @Override public boolean isEmpty() { return mappings.isEmpty(); } @Override public Iterator<Mapping> iterator() { return mappings.iterator(); } @Override public String serialize() { return Joiner.on(';').join(asStrings()); } private Predicate<Mapping> hasType(final Mapping.Type type) { return new Predicate<Mapping>() { @Override public boolean apply(Mapping input) { return input.getType().equals(type); } }; } @Override public boolean contains(Type type) { Preconditions.checkNotNull(type); return FluentIterable.from(mappings).anyMatch(hasType(type)); } @Override public Mappings select(Type type) { Preconditions.checkNotNull(type); return fromMappings(FluentIterable.from(mappings).filter(hasType(type))); } @Override public Mappings exclude(Type type) { Preconditions.checkNotNull(type); return fromMappings(FluentIterable.from(mappings).filter(Predicates.not(hasType(type)))); } @Override public Mapping getError() { Mappings errors = select(Type.Error); Preconditions.checkState(!errors.isEmpty()); return Iterables.getFirst(errors, null); } @Override public Optional<Mappings> toOptional() { if (isEmpty()) { return Optional.absent(); } return Optional.<Mappings>of(this); } @Override public Mappings union(Mappings mappings) { Preconditions.checkState(mappings != null, "mappings is mandatory"); return from(this).addAll(mappings).build(); } @Override public int hashCode() { return Objects.hashCode(mappings); } @Override public boolean equals(Object obj) { if (obj instanceof MappingsImpl) { MappingsImpl other = (MappingsImpl) obj; return Objects.equal(mappings, other.mappings); } return false; } @Override public String toString() { return MoreObjects.toStringHelper(getClass()).add("mappings", mappings).toString(); } }