我正在尝试从 IMDB 中解析制表符分隔的值转储。 (The actual dump 每行包含的制表符数量不一致。):
$, Claw "OnCreativity" (2012) [Himself]
$, Homo Nykytaiteen museo (1986) [Himself] <25>
Suuri illusioni (1985) [Guests] <22>
$hutter Battle of the Sexes (2017) (as $hutter Boy) [Bobby Riggs Fan] <10>
NVTION: The Star Nation Rapumentary (2016) (as $hutter Boy) [Himself] <1>
Secret in Their Eyes (2015) (uncredited) [2002 Dodger Fan]
Steve Jobs (2015) (uncredited) [1988 Opera House Patron]
Straight Outta Compton (2015) (uncredited) [Club Patron/Dopeman]
$lim, Bee Moe Fatherhood 101 (2013) (as Brandon Moore) [Himself - President, Passages]
For Thy Love 2 (2009) [Thug 1]
Night of the Jackals (2009) (V) [Trooth]
"Idle Talk" (2013) (as Brandon Moore) [Himself]
"Idle Times" (2012) {(#1.1)} (as Brandon Moore)
$ly, Yung Town Bizzness Pt 3 (2014) (V) [Yung $ly]
"From Tha Bottom 2 Tha Top" (2016) [Yung $ly]
"From Tha Bottom 2 Tha Top" (2016) {T-Pain (#1.2)} [Yung $ly]
$torm, Cuntry From the Woods: The Discovery of LYB (????) (as Country $torm) [Himself]
& Davi, Bruninho Michel na Balada (2011) (V) [Themselves]
Michel TelÛ: Sunset (2013) (V) [Themselves]
"Programa da Sabrina" (2014) {(2016-01-23)} [Themselves]
& Dollar Furado, Caio Corsalette "Som Brasil" (2007) {ZezÈ di Camargo & Luciano (#5.7)} [Themselves]
& Fabiano, CÈsar Menotti Nascemos para Cantar (2010) (TV) [Themselves]
Show da Virada (2011) (TV) [Themselves - Performers]
Teleton 2010 (2010) (TV) [Themselves]
"Altas Horas" (2000) {(2013-06-29)} [Themselves]
"Altas Horas" (2000) {(2013-12-14)} [Themselves]
"Eliana" (2009) {(2012-10-21)} [Themselves]
"Tudo … PossÌvel" (2005) {(2008-04-13)} [Themselves]
"TV Xuxa" (2005) {(2013-01-05)} [Themselves]
我的代码:
package com.mycompany.imdbproject;
import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class ActorListParser {
Charset charset = Charset.forName("ISO-8859-1");
BufferedReader reader = null;
public ActorListParser() {
try {
this.reader = Files.newBufferedReader(
new File(System.getProperty("user.home") + ("/IMDBLogs" + "/dataDirectory" + "/acsshort.txt")).toPath(), charset);
String line = null;
while ((line = reader.readLine()) != null) {
String[] lineAsArray = null;
Pattern startsWithTab = Pattern.compile("^\t.*$");
Matcher tab = startsWithTab.matcher(line);
boolean startsWithTabMatcher = tab.matches();
if (!startsWithTabMatcher) {
lineAsArray = line.split("\t");
for (int i = 0;i < lineAsArray.length; i++) {
System.out.println("Length: " + lineAsArray.length +", Value:"+ i +" "+ lineAsArray[i]);
}
}else{
//parse lines that start with a tab (actor's other movies)
}
}
} catch (IOException ex) {
Logger.getLogger(ActorListParser.class.getName()).log(Level.SEVERE, null, ex);
}
}
public static void main(String[] args) {
ActorListParser acp = new ActorListParser();
}
}
输出:
Length: 2, Value:0 $, Claw
Length: 2, Value:1 "OnCreativity" (2012) [Himself]
Length: 1, Value:0
Length: 2, Value:0 $, Homo
Length: 2, Value:1 Nykytaiteen museo (1986) [Himself] <25>
Length: 1, Value:0
Length: 2, Value:0 $hutter
Length: 2, Value:1 Battle of the Sexes (2017) (as $hutter Boy) [Bobby Riggs Fan] <10>
Length: 1, Value:0
Length: 2, Value:0 $lim, Bee Moe
Length: 2, Value:1 Fatherhood 101 (2013) (as Brandon Moore) [Himself - President, Passages]
Length: 1, Value:0
Length: 2, Value:0 $ly, Yung
Length: 2, Value:1 Town Bizzness Pt 3 (2014) (V) [Yung $ly]
Length: 1, Value:0
Length: 2, Value:0 $torm, Cuntry
Length: 2, Value:1 From the Woods: The Discovery of LYB (????) (as Country $torm) [Himself]
Length: 1, Value:0
Length: 2, Value:0 & Davi, Bruninho
Length: 2, Value:1 Michel na Balada (2011) (V) [Themselves]
Length: 1, Value:0
Length: 2, Value:0 & Dollar Furado, Caio Corsalette
Length: 2, Value:1 "Som Brasil" (2007) {Zezà di Camargo & Luciano (#5.7)} [Themselves]
Length: 1, Value:0
Length: 2, Value:0 & Fabiano, CÃsar Menotti
Length: 2, Value:1 Nascemos para Cantar (2010) (TV) [Themselves]
如您所见,我获取了作者姓名的第一次出现,并从中解析出姓名和电影。(以便稍后在 map 中使用)。我将在单独的正则表达式中获取归因于该 Actor 的其他电影。
不幸的是,有一个长度为 1 且没有值的数组一直出现在我的输出中。我做错了什么,创建了这个空数组?
最佳答案
输入中有空行。它们不以制表符开头,因此它们与 if
语句匹配。然后,在任何内容上分割一个空行将产生一个长度为 1 且包含空字符串元素的数组。例如,"".split("blah")
返回一个长度为 1 的数组,其中包含一个空字符串元素。这就是 String.split
的工作方式。
因此,解决方案是添加对 !line.isEmpty()
的检查。
@Andreas 在评论中说得最好:
Yup. See javadoc: If the expression does not match any part of the input then the resulting array has just one element, namely this string.
关于java - 正则表达式正在创建一个不应该存在的空数组,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/38491698/