Java关于Strning的indexOf与contains方法的区别

偶然看到一些文章有关java中String的indexOf与contains效率的比较,翻了一些大多数测试表示indexOf效率相对contains很快,随即翻看源码的过程发现contains方法其实是直接调用的indexOf方法,所以个人觉得还是看方法的用途,contains也就比indexOf多一层方法栈,附源码:

//jdk8
/**
 * Returns true if and only if this string contains the specified
 * sequence of char values.
 *
 * @param s the sequence to search for
 * @return true if this string contains {@code s}, false otherwise
 * @since 1.5
 */
public boolean contains(CharSequence s) {
    return indexOf(s.toString()) > -1;
}

//jdk11
/**
 * Returns true if and only if this string contains the specified
 * sequence of char values.
 *
 * @param s the sequence to search for
 * @return true if this string contains {@code s}, false otherwise
 * @since 1.5
 */
public boolean contains(CharSequence s) {
    return indexOf(s.toString()) >= 0;
}