Eliminating Code Overhead by Jake Wharton

https://www.youtube.com/watch?v=b6zKBZcg5fk
笔记:

1. new ArrayList<>(), 最好是给初始的capacity, 默认值是zero initial capacity.
   尽量避免之后调用add()操作， 造成的memory object copy引起的额外性能消耗.
   chromium写的好的代码长这样:

    protected static List processLogcat(List rawLogcat) {
        List out = new ArrayList(rawLogcat.size());
        for (String ln : rawLogcat) {
            ln = elideEmail(ln);
            ln = elideUrl(ln);
            ln = elideIp(ln);
            ln = elideMac(ln);
            ln = elideConsole(ln);
            out.add(ln);
        }
        return out;
    }

2. new StringBuilder(), 最好给出初始的capacity, 默认值是16.
   尽量避免之后调用append()操作， 造成的memory object copy引起的额外性能消耗.
   最好是调用这个构造方法:

    public StringBuilder(String str) {
        super(str);
    }

The capacity of the new builder will be the length of the String plus 16.
chromium写的好的代码长这样:

    private String buildSuggestWhere(String selection, int argc) {
        StringBuilder sb = new StringBuilder(selection);
        for (int i = 0; i < argc - 1; i++) {
            sb.append(" OR ");
            sb.append(selection);
        }
        return sb.toString();
    }

3. 学习了不同的方法调用对应bytecode上的4种类型.

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----- DONE ----