问题
发现程序开机启动慢，仔细调查，意外发现了fastjson解析慢的问题
使用fastjson版本
compile 'com.alibaba:fastjson:1.2.32'
示例说明
// 在一个单元测试的case里 写代码验证
@Test
public void addition_isCorrect() throws Exception {
assertEquals(4, 2 + 2);
test("空字符串", new Runnable() {
@Override
public void run() {
List<String> strs = JSON.parseArray("", String.class);
}
});
test("[]", new Runnable() {
@Override
public void run() {
List<String> strs = JSON.parseArray("[]", String.class);
}
});
test("[\"a\"]", new Runnable() {
@Override
public void run() {
List<String> strs = JSON.parseArray("[\"a\"]", String.class);
}
});
}
public void test(String name, Runnable runnable) {
long time = System.currentTimeMillis();
runnable.run();
System.out.println(name + " cost " + (System.currentTimeMillis() - time) + "\n");
}
输出结果如下
空字符串 cost 92
[] cost 0
["a"] cost 0
简直不敢相信空字符串竟然耗时92ms
尝试修改了代码和顺序结果如下
{"a":"hello","b":2} cost 107
["a"] cost 0
["a"] again cost 0
[] cost 0
空字符串 cost 0
再修改顺序
["a"] cost 103
["a"] again cost 0
{"a":"hello","b":2} cost 16
[] cost 0
空字符串 cost 0
[] cost 79
["a"] cost 0
["a"] again cost 0
{"a":"hello","b":2} cost 10
空字符串 cost 0
发现原来第一次解析比较耗时
