版本
JDK8(JDK1.8)

Predicate接口源码重点
1.Predicate（谓词）是一个函数式接口，即接口里只一一个抽象方法 boolean test(T t)，其他都是默认方法和静态方法

2.实现Predicate的实现类可以重写text(T t)方法定义自己的规则，传入元素t符合自己的规则返回true，否则返回false

3.Predicate接口定义的部分方法

Predicate接口源码

package java.util.function;

import java.util.Objects;

/**
 * Represents a predicate (boolean-valued function) of one argument.
 * 表示一个参数的谓词（布尔值函数）。 （谓词代表一种规则）
 * <p>This is a <a href="package-summary.html">functional interface</a>
 * whose functional method is {@link #test(Object)}.
 * 这是一个函数接口，其函数方法是test(Object)。
 * @param <T> the type of the input to the predicate 谓词的输入类型
 *
 * @since 1.8
 */
@FunctionalInterface
public interface Predicate<T> {

    /**
     * Evaluates this predicate on the given argument. 对给定参数计算此谓词。(即判断参数符不符合该规则)
     *
     * @param t the input argument 输入参数
     * @return {@code true} if the input argument matches the predicate,
     * otherwise {@code false} 如果输入参数与谓词匹配，则为true，否则为false
     */
    boolean test(T t);

    /**
     * Returns a composed predicate that represents a short-circuiting logical
     * AND of this predicate and another.  When evaluating the composed
     * predicate, if this predicate is {@code false}, then the {@code other}
     * predicate is not evaluated.
     * 返回一个组合谓词，该谓词表示此谓词和另一个谓词的短路逻辑AND。
     * 计算组合谓词时，如果此谓词为false，则不计算other谓词。
     * 
     *
     * <p>Any exceptions thrown during evaluation of either predicate are relayed
     * to the caller; if evaluation of this predicate throws an exception, the
     * {@code other} predicate will not be evaluated.
     * 在对任一谓词求值期间抛出的任何异常都将转发给调用方；
     * 如果对该谓词的求值引发异常，other谓词将不会求值。
     *
     * @param other a predicate that will be logically-ANDed with this
     *              predicate 将与此谓词逻辑AND的谓词
     * @return a composed predicate that represents the short-circuiting logical
     * AND of this predicate and the {@code other} predicate
     * 返回一种组合谓词，表示该谓词和other谓词的短路逻辑AND
     * 实质是用两个Predicate的test()方法使用逻辑运算符组合在一起
     * @throws NullPointerException if other is null
     */
    default Predicate<T> and(Predicate<? super T> other) {
        // 判断other是否为空，是抛出异常
        Objects.requireNonNull(other);
        return (t) -> test(t) && other.test(t);
    }

    /**
     * Returns a predicate that represents the logical negation of this
     * predicate. 返回表示此谓词逻辑否定的谓词。
     *
     * @return a predicate that represents the logical negation of this
     * predicate 表示该谓词的逻辑否定的谓词
     */
    default Predicate<T> negate() {
        return (t) -> !test(t);
    }

    /**
     * Returns a composed predicate that represents a short-circuiting logical
     * OR of this predicate and another.  When evaluating the composed
     * predicate, if this predicate is {@code true}, then the {@code other}
     * predicate is not evaluated. 
     * 返回表示此谓词和另一个谓词的短路逻辑OR的组合谓词。
     * 计算组合谓词时，如果此谓词为true，则不计算other谓词。
     *
     * <p>Any exceptions thrown during evaluation of either predicate are relayed
     * to the caller; if evaluation of this predicate throws an exception, the
     * {@code other} predicate will not be evaluated.
     * 在对任一谓词求值期间抛出的任何异常都将转发给调用方；
     * 如果对该谓词的求值引发异常，other谓词将不会求值。
     *
     * @param other a predicate that will be logically-ORed with this
     *              predicate 将与此谓词进行逻辑或运算的谓词
     * @return a composed predicate that represents the short-circuiting logical
     * OR of this predicate and the {@code other} predicate 
     * 表示该谓词和ther谓词的短路逻辑OR的组合谓词
     * @throws NullPointerException if other is null
     */
    default Predicate<T> or(Predicate<? super T> other) {
        Objects.requireNonNull(other);
        return (t) -> test(t) || other.test(t);
    }

    /**
     * Returns a predicate that tests if two arguments are equal according
     * to {@link Objects#equals(Object, Object)}.
     * 返回一个谓词，该谓词根据Objects.equals(Object，Object)测试两个参数是否相等。
     * 
     *
     * @param <T> the type of arguments to the predicate 谓词的参数类型
     * @param targetRef the object reference with which to compare for equality,
     *               which may be {@code null} 
     *  用于比较相等性的对象引用，该引用可以是null
     * @return a predicate that tests if two arguments are equal according
     * to {@link Objects#equals(Object, Object)}
     * 根据Objects.equals(Object，Object)测试两个参数是否相等的谓词
     */
    static <T> Predicate<T> isEqual(Object targetRef) {
        return (null == targetRef)
                ? Objects::isNull
                : object -> targetRef.equals(object);
    }

    /**
     * Returns a predicate that is the negation of the supplied predicate.
     * This is accomplished by returning result of the calling
     * {@code target.negate()}.
     * 返回对提供的谓词求反的谓词。这是通过返回调用target.negate()的结果来实现的。
     * @param <T>     the type of arguments to the specified predicate
     *                 指定谓词的参数类型
     * @param target  predicate to negate 否定谓词
     *
     * @return a predicate that negates the results of the supplied
     *         predicate 对提供的谓词的结果求反的谓词
     *
     * @throws NullPointerException if target is null 如果目标为空
     *
     * @since 11
     */
    @SuppressWarnings("unchecked")
    static <T> Predicate<T> not(Predicate<? super T> target) {
        Objects.requireNonNull(target);
        return (Predicate<T>)target.negate();
    }
}