Java8謂詞如果有其他返回

Question

如何爲下面的代碼編寫Java 8謂詞？

public boolean isArtOrNot(int aId) { 
    if(aid <= 4) { 
     return true; 
    } else { 
    return false; 
    } 
} 

Answer 1

t -> t <= 4 

例如

example.stream().filter(t -> t <= 4) 

因爲例子等價於：

public boolean isArtOrNot(int aId) { 
    return aid <= 4; 
} 

Answer 2

簡單：

IntPredicate predicate = i -> i <= 4; 

Answer 3

Predicate<Integer> isArt = (i) -> i <= 4; 

Answer 4

要添加到Marcel Jacques Machado's answer：

Predicate<Integer> isArt = (i) -> i <= 4; 

實施謂詞如下：

if (isArt.test()) { .... .... }