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Groovy:带有嵌入引号的字符串不能按预期执行

groovy

Charlie Martin · 技术社区 · 14 年前

这很奇怪:使用groovy字符串保存一些命令行以执行,我发现有时如果字符串中有引号字符,则执行将失败。

print " 1: " ; "grep nameserver /etc/resolv.conf".execute().text.eachLine {println it }          ; println ""
print " 2: " ; "grep 'nameserver' /etc/resolv.conf".execute().text.eachLine {println it }        ; println ""
print " 3: " ; """grep nameserver /etc/resolv.conf""".execute().text.eachLine {println it }      ; println ""
print " 4: " ; """grep "nameserver" /etc/resolv.conf""".execute().text.eachLine {println it }    ; println ""
print " 5: " ; """grep 'nameserver' /etc/resolv.conf""".execute().text.eachLine {println it }    ; println ""
print " 6: " ; "awk /nameserver/ /etc/resolv.conf".execute().text.eachLine{ println it }         ; println ""
print " 7: " ; "awk '/nameserver/' /etc/resolv.conf".execute().text.eachLine{ println it }       ; println ""
print " 8: " ; """awk "/nameserver/" /etc/resolv.conf""".execute().text.eachLine{ println it }   ; println ""
print " 9: " ; """awk '/nameserver/' /etc/resolv.conf""".execute().text.eachLine{ println it }   ; println ""
print "10: " ; """awk "/nameserver/{print \$2}" /etc/resolv.conf""".execute().text.eachLine{ println it }   ; println ""
return

结果如下:

$ groovy weird.groovy 
 1: nameserver 10.3.0.101
nameserver 10.4.1.237
nameserver 10.2.1.34

 2: 
 3: nameserver 10.3.0.101
nameserver 10.4.1.237
nameserver 10.2.1.34

 4: 
 5: 
 6: nameserver 10.3.0.101
nameserver 10.4.1.237
nameserver 10.2.1.34

 7: 
 8: nameserver 10.3.0.101
nameserver 10.4.1.237
nameserver 10.2.1.34
domain lnx.copansys.com
search lnx.copansys.com tst.copansys.com copansys.com

 9: 
10:

下面是另一个例子:

"bash -c echo Hello".execute().text.eachLine{ println it }
"bash -c echo 'Hello'".execute().text.eachLine{ println it }
"bash -c echo \'Hello\'".execute().text.eachLine{ println it }

结果:

groovy> "bash -c echo Hello".execute().text.eachLine{ println it } 
groovy> "bash -c echo 'Hello'".execute().text.eachLine{ println it } 
groovy> "bash -c echo \'Hello\'".execute().text.eachLine{ println it } 

'Hello!'

请注意,嵌入反斜杠引号“似乎没有帮助。

2 回复 | 直到 14 年前

ataylor 9 年前

执行命令时 String.execute() ,它们不会被命令shell解析。引号传递给实际执行的命令;在本例中是grep和awk。

用echo替换grep和awk可以说明这一点:

print " 1: " ; "echo something".execute().text.eachLine {println it }          ; println ""
print " 2: " ; "echo 'something'".execute().text.eachLine {println it }        ; println ""
print " 3: " ; """echo something""".execute().text.eachLine {println it }      ; println ""
print " 4: " ; """echo "something" """.execute().text.eachLine {println it }   ; println ""
print " 5: " ; """echo 'something'""".execute().text.eachLine {println it }    ; println ""

 1: something

 2: 'something'

 3: something

 4: "something"

 5: 'something'

一个简单的解决方法是将命令行构建为字符串列表:

["awk", 'BEGIN { print "hello" }'].execute().text

如果您需要更好地控制命令的解析方式,请查看 ProcessBuilder 是围绕着它建造的。

Vadim Kotov First Zero 7 年前

http://docs.groovy-lang.org/latest/html/documentation/index.html#all-strings
"'" ( ' )以及 """"""" ( " )您所期望的在groovy中不存在,所以或 " \' \"