com.totsp.tom.Tom.java Source code

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Here is the source code for com.totsp.tom.Tom.java

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/**
 *    Copyright 2013 Robert Cooper
 *
 *    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.totsp.tom;

import com.google.common.base.Function;
import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;
import com.totsp.gwittir.introspection.Introspector;
import com.totsp.tom.functions.PropertiesSelectorFunction;
import com.totsp.tom.functions.PropertySelectionFunction;
import com.totsp.tom.interfaces.Finally;
import com.totsp.tom.interfaces.From;
import com.totsp.tom.interfaces.Select;
import com.totsp.tom.interfaces.Where;
import com.totsp.tom.predicates.All;
import com.totsp.tom.predicates.Any;
import com.totsp.tom.predicates.Contains;
import com.totsp.tom.predicates.Equals;
import com.totsp.tom.predicates.GreaterThan;
import com.totsp.tom.predicates.GreaterThanOrEqual;
import com.totsp.tom.predicates.LessThan;
import com.totsp.tom.predicates.LessThanOrEqual;
import com.totsp.tom.predicates.Not;
import com.totsp.tom.util.Functions;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;

import static com.google.common.base.Preconditions.checkNotNull;

/**
 *
 */
public class Tom<T> implements Select<T>, From<T>, Where<T>, Finally<T>, Serializable {

    private static Introspector INTROSPECTOR;

    private Iterable<T> source;
    private Function<T, ?> selector;

    private Tom() {
        super();
    }

    public Where<T> from(Iterable<? extends Object> collection) {
        this.source = (Iterable<T>) collection;
        return this;
    }

    public Finally<T> where(Predicate<T> predicate) {
        this.source = Iterables.filter(this.source, predicate);
        return this;
    }

    @Override
    public Finally<T> every() {
        return this;
    }

    @Override
    public From select() {
        this.selector = (Function<T, ?>) Functions.IDENTITY;
        return this;
    }

    @Override
    public From select(String propertyExpression) {
        checkNotNull(propertyExpression, "You must provide at least one property expression.");
        this.selector = new PropertySelectionFunction<T>(propertyExpression);
        return this;
    }

    @Override
    public From select(String propertyExpression, String... propertyExpressions) {
        checkNotNull(propertyExpression, "You must provide at least one property expression.");
        ArrayList<String> list = new ArrayList<String>(
                1 + (propertyExpression == null ? 0 : propertyExpression.length()));
        list.add(propertyExpression);
        if (propertyExpressions != null) {
            Collections.addAll(list, propertyExpressions);
        }
        this.selector = new PropertiesSelectorFunction<T>(list);
        return this;
    }

    @Override
    public From<T> select(@Nonnull Function<T, ?> selector) {
        this.selector = selector;
        return this;
    }

    @Override
    public <R> Iterable<R> asIterable() {
        return Iterables.transform(source, (Function<? super T, ? extends R>) this.selector);
    }

    @Override
    public <C extends Collection<?>> C into(C collection) {
        Iterables.addAll((Collection) collection, asIterable());
        return collection;
    }

    public static void initialize(Introspector introspector) {
        INTROSPECTOR = introspector;
    }

    public static <T, P extends Serializable, R extends Predicate<T> & Serializable> R eq(String propertyExpression,
            P value) {
        return (R) new Equals<T, P>(value, propertyExpression);
    }

    public static <T, P extends Comparable & Serializable, R extends Predicate<T> & Serializable> R lt(
            @Nonnull String propertyExpression, @Nullable P value) {
        checkNotNull(propertyExpression, "You must supply a property expression.");
        return (R) new LessThan<T, P>(value, propertyExpression);
    }

    public static <T, P extends Comparable & Serializable, R extends Predicate<T> & Serializable> R ltEq(
            @Nonnull String propertyExpression, @Nullable P value) {
        checkNotNull(propertyExpression, "You must supply a property expression.");
        return (R) new LessThanOrEqual<T, P>(value, propertyExpression);
    }

    public static <T, P extends Comparable & Serializable, R extends Predicate<T> & Serializable> R gt(
            @Nonnull String propertyExpression, @Nullable P value) {
        checkNotNull(propertyExpression, "You must supply a property expression.");
        return (R) new GreaterThan<T, P>(value, propertyExpression);
    }

    public static <T, P extends Comparable & Serializable, R extends Predicate<T> & Serializable> R gtEq(
            @Nonnull String propertyExpression, @Nullable P value) {
        checkNotNull(propertyExpression, "You must supply a property expression.");
        return (R) new GreaterThanOrEqual<T, P>(value, propertyExpression);
    }

    public static <T, P extends Predicate<T> & Serializable, R extends Predicate<T> & Serializable> R not(
            @Nonnull P predicate) {
        checkNotNull(predicate, "You must supply a predicate function");
        return (R) new Not<T>(predicate);
    }

    public static <T, P extends Serializable, R extends Predicate<T> & Serializable> R contains(
            @Nonnull String propertyExpression, @Nullable P value) {
        checkNotNull(propertyExpression, "You must supply a property expression.");
        return (R) new Contains<T, P>(value, propertyExpression);
    }

    public static <T> Select<T> tom() {
        return new Tom<T>();
    }

    public static <T> Predicate<T> anyOf(Predicate<T>... predicates) {
        return new Any<T>(predicates);
    }

    public static <T> Predicate<T> allOf(Predicate<T>... predicates) {
        return new All<T>(predicates);
    }

    public static Introspector getIntrospector() {
        return INTROSPECTOR;
    }
}