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Java in English · for a complete beginner英文 Java · 写给完全零基础

One small page. One idea.一次只读一页,一次只学一个概念。

I know nothing about Java. I want to learn it in English, not in Chinese. So every page gives one idea, five new words, and three questions I answer out loud.我不懂 Java,而且我想用英文学,不是用中文背。所以每一页只讲一个概念、给五个新词、三道要出声回答的题。

Short answer先给答案This site teaches Java in English, one question per page. Pick a question; when a word or an idea is missing, the page says which lesson to read first.这个站用英文教 Java,一页一个问题。先挑一道题读;卡在哪个词、哪个概念,页面会告诉你先补哪一节课。

3 questions3 道题7 lessons7 节课

01Three interview questions三道面试题

Three for now, all taken from my own résumé. Each one is a page: a 60-second answer, the mechanism behind it, and the new questions it opens.现在三道,全部从我的简历里挖出来的。一道一页:60 秒答案、背后的机制、以及它又长出了哪些新问题。

A fourth one gets added when the third one is solid.第三道读透了再加第四道。

02The ground: seven lessons地基:七节课

If a word in an answer is missing, the page tells you which lesson to read first. These are the seven pieces.答案里哪个词不认识,页面会告诉你先补哪一节课。就是这七块。

1 数组 · 2 链表 · 3 树 / 红黑树 · 4 key / hash / 冲突 · 5 O(1) / O(n) / O(log n) · 6 HashMap 常用方法 · 7 为什么线程不安全

03How to read a page怎么读一页

  1. Press 🔊 at the top. Follow the words with your eyes. Twice is enough.点页面顶部的 🔊,眼睛跟着字走。两遍就够。
  2. Switch to 中英 if a sentence is too hard. Read the English first, then the Chinese.句子太难就切到 中英:先读英文,再看中文。
  3. Read the 60-second answer, then the mechanism. The new questions are at the bottom of the page.先读 60 秒答案,再读机制。新问题在同一页的底部。
  4. Answer the three questions at the end out loud, not in your head.最后三道自测要出声回答,不要只在心里想。

Twenty minutes a page. One page a day is enough.一页二十分钟。一天一页就够。

04Why English, and why so slow为什么要英文、为什么这么慢

In an interview the words are English: bucket, collision, resize. If I only know the Chinese word, I hear a sound I cannot follow.面试里蹦出来的是英文词:bucket、collision、resize。如果我只知道中文说法,听到的就是一串抓不住的声音。

So this site is slow on purpose. One question per page, five words, one picture.所以这个网站是故意慢的:一页一道题、五个词、一张图。

→New words新词

bucket /ˈbʌkɪt/ One box in the array.桶:数组里的一格 ▶ hear it
collision /kəˈlɪʒn/ Two keys that land in the same bucket.冲突:两个 key 落进同一个桶 ▶ hear it
resize /ˌriːˈsaɪz/ Make the array bigger and move items.扩容:把数组变大并搬数据 ▶ hear it
thread /θred/ One worker inside a program.线程:程序里的一个干活的 ▶ hear it
complexity /kəmˈpleksəti/ How cost grows with size.复杂度:代价随数据量的增长方式 ▶ hear it

Click ▶ hear it for real people on YouGlish; 🔊 for the computer voice.点 ▶ hear it 听真人发音(YouGlish);点 🔊 听电脑朗读。

✓Check yourself自测

  1. Say the plan for today in one sentence.用一句话说出今天要做的事。
  2. Which page are you reading today?今天你读哪一页?
  3. Say one word you learned, out loud.说出一个今天学的词,出声。

Answer out loud first. Only then open the answers below.先自己出声答,再看下面的答案。

Answers参考答案
01I read one page, learn five words, and answer three questions out loud.今天要做的事:读一页、学五个词、出声答三道题。
02Start with Lesson 1, “What is an array?”.从第 1 课开始:什么是数组。
03bucket — one box of the array.bucket:数组里的一格。

Start Lesson 1 →开始第 1 课 →