循环使用正则导致进程挂起和cpu使用率达到100%居高不下测试Demo
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class ErrorDataStatTest {
public static Map<String,EntryBean> errorMap = new HashMap<String,EntryBean>();
public static void main(String[] args) {
String dest = "/Users/kevin/Documents/shop.do1";
try {
new ErrorDataStattest().statData(new File(dest));
} catch (IOException e) {
e.printstacktrace();
}
for (Map.Entry<String,EntryBean> entry : errorMap.entrySet()) {
System.out.println(entry.getKey() + "\t" + entry.getValue().val + "\t" + entry.getValue().num);
}
}
public static class EntryBean {
String key;
String val;
int num = 0;
public EntryBean(String key,String val) {
this.key = key;
this.val = val;
}
public void add() {
this.num++;
}
}
public static final String regex_code = ".*?code.*?=.*?\"(-?[\\d]*)\"";
public static final Pattern pattern = Pattern.compile(regex_code);
public static final String regex_code_1 = ".*?Code\\s?=\\s?(-?[\\d]*).*?";
public static final Pattern pattern_1 = Pattern.compile(regex_code_1);
//解析错误Code
private static String parserErrorCode(String error) {
Matcher matcher = pattern.matcher(error);
if (matcher.find()) {
return matcher.group(1);
}
Matcher matcher1 = pattern_1.matcher(error);
if (matcher1.find()) {
return matcher1.group(1);
}
return null;
}
public static final String regex_desc = ".*?description.*?=.*?\"(.*?)\"";
public static final Pattern pattern_desc = Pattern.compile(regex_desc);
private static final String regex_desc_1 = ".*?Code\\s?=\\s?[-]?[\\d]*\\s*\"(.*?)\".*?";
private static final Pattern pattern_desc_1 = Pattern.compile(regex_desc_1);
//解析错误描述
private static String parserErrorDesc(String error) {
Matcher matcher = pattern_desc.matcher(error);
if (matcher.find()) {
return matcher.group(1);
}
Matcher matcher1 = pattern_desc_1.matcher(error);
if (matcher1.find()) {
return matcher1.group(1);
}
return null;
}
private String process(String str) {
if (str != null) {
String key = parserErrorCode(str),val = parserErrorDesc(str);
EntryBean entryBean = errorMap.get(key);
if (entryBean == null) {
entryBean = new EntryBean(key,val);
} else {
entryBean.add();
}
errorMap.put(key,entryBean);
}
return str;
}
/*统计日志文件：按照错误码分类统计汇总*/
protected void statData(File srcFile) throws IOException {
FileReader reader = new FileReader(srcFile);
BufferedReader bReader = new BufferedReader(reader);
try {
String line = process(bReader.readLine());
int num = 0;
while (line != null) {
line = process(bReader.readLine());
System.out.println(num);
num++;
}
} catch (FileNotFoundException ex) {
throw ex;
} finally {
bReader.close();
bReader = null;
reader.close();
reader = null;
}
}
}
本地测试了几次都是在循环处理到第11497次的时候程序卡住不动，导致进程挂起，cpu消耗在100%左右一直下不来。
localhost:~ kevin$ jstack 675
2014-03-22 11:10:16
Full thread dump Java HotSpot(TM) 64-Bit Server VM (24.45-b08 mixed mode):
"Attach Listener" daemon prio=5 tid=0x00007f96638e9000 nid=0x3c0b waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Service Thread" daemon prio=5 tid=0x00007f966301e000 nid=0x4b03 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C2 CompilerThread1" daemon prio=5 tid=0x00007f966301d000 nid=0x4903 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C2 CompilerThread0" daemon prio=5 tid=0x00007f966300d000 nid=0x4703 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Signal dispatcher" daemon prio=5 tid=0x00007f9663014000 nid=0x4503 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Finalizer" daemon prio=5 tid=0x00007f9664827000 nid=0x3103 in Object.wait() [0x000000011108c000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000007eaa85568> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
- locked <0x00000007eaa85568> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:151)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:189)
"Reference Handler" daemon prio=5 tid=0x00007f9664029000 nid=0x2f03 in Object.wait() [0x0000000110f89000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000007eaa850f0> (a java.lang.ref.Reference$Lock)
at java.lang.Object.wait(Object.java:503)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:133)
- locked <0x00000007eaa850f0> (a java.lang.ref.Reference$Lock)
"main" prio=5 tid=0x00007f9664800000 nid=0x1903 runnable [0x0000000109753000]
java.lang.Thread.State: RUNNABLE
at java.util.regex.Pattern$Curly.match1(Pattern.java:4198)
at java.util.regex.Pattern$Curly.match(Pattern.java:4134)
at java.util.regex.Pattern$start.match(Pattern.java:3408)
at java.util.regex.Matcher.search(Matcher.java:1199)
at java.util.regex.Matcher.find(Matcher.java:592)
at com.ishopping.sign.controller.ErrorDataStatTest.parserErrorDesc(ErrorDataStatTest.java:72)
at com.ishopping.sign.controller.ErrorDataStatTest.process(ErrorDataStatTest.java:84)
at com.ishopping.sign.controller.ErrorDataStatTest.statData(ErrorDataStatTest.java:140)
at com.ishopping.sign.controller.ErrorDataStatTest.main(ErrorDataStatTest.java:24)
"VM Thread" prio=5 tid=0x00007f9664028800 nid=0x2d03 runnable
"GC task thread#0 (ParallelGC)" prio=5 tid=0x00007f966300f800 nid=0x2503 runnable
"GC task thread#1 (ParallelGC)" prio=5 tid=0x00007f9663010800 nid=0x2703 runnable
"GC task thread#2 (ParallelGC)" prio=5 tid=0x00007f9663011000 nid=0x2903 runnable
"GC task thread#3 (ParallelGC)" prio=5 tid=0x00007f9663011800 nid=0x2b03 runnable
"VM Periodic Task Thread" prio=5 tid=0x00007f9663019800 nid=0x4d03 waiting on condition
JNI global references: 181
ORACLE:
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5050507和http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6988218
#总结
建议在高频度执行的代码或高并发的系统中尽量少的使用正则。
