遍歷集合的幾種方式

list list=

newarraylist
<
>()
;

iterator

it=list.
iterator()
;while
(it.
hasnext()
)

for

(string ele:list)

list.

foreach
(e-> system.out.
println
(e))
;

for

(int i =
0; i size()
; i++
)

1：無非就是通過map.keyset()獲取到值，然後根據鍵獲取到值

for

(string s:map.
keyset()
)

for

(map.entry
entry : map.
entryset()
)

iterator

> it=map.
entryset()
.iterator()
;while
(it.
hasnext()
)

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