Java属性：如何转义#（散列）

Question

如何在Java属性文件中转义哈希符号（#）

我们有一个使用Java属性文件的国际化框架

有一个名为number的列，我们希望它的标题为#。这个

number=#

。。。不起作用

Answer 1

由于Java中的默认转义字符是'\'，请尝试用它转义散列

Answer 2

哈希（#）在属性文件中用\字符转义。例如，要将键#foo映射到值#bar，您可以编写：

\#foo=\#bar

它适用于键和值，尽管（如其他答案中所暗示的）值并不严格要求它

Answer 3

此选项应在没有任何转义字符的情况下工作：

number=#

刚刚用代码做了一个小测试

prop.load(new FileInputStream ("./res/app.properties"));
System.out.println("Property: " +prop.getProperty("Number"));

。。。和属性文件（注意大写/小写）：

Number=#
Text=test

结果:

Property: #

因此，请检查您的拼写、大小写或进一步处理

查看this或that one（也链接Java文档）了解更多信息

p.s.：虽然不需要它，但您也可以尝试Unicode序列：\u0023

干杯

Answer 4

在以下情况下，我在寻找如何正确逃生时发现了这个问题（不起作用）：

zendesk.ticket.subject.prefix=#{{ticket.id}}

在这种情况下，它需要转义，否则会发生以下异常：

Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'createTicketService' defined in file [/Users/***]: Unsatisfied dependency expressed through constructor parameter 6; nested exception is org.springframework.beans.factory.BeanExpressionException: Expression parsing failed; nested exception is org.springframework.expression.spel.SpelEvaluationException: EL1008E: Property or field 'ticket' cannot be found on object of type 'org.springframework.beans.factory.config.BeanExpressionContext' - maybe not public?
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:749)
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:189)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1193)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1095)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:835)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741)
    ... 64 common frames omitted
Caused by: org.springframework.beans.factory.BeanExpressionException: Expression parsing failed; nested exception is org.springframework.expression.spel.SpelEvaluationException: EL1008E: Property or field 'ticket' cannot be found on object of type 'org.springframework.beans.factory.config.BeanExpressionContext' - maybe not public?
    at org.springframework.context.expression.StandardBeanExpressionResolver.evaluate(StandardBeanExpressionResolver.java:164)
    at org.springframework.beans.factory.support.AbstractBeanFactory.evaluateBeanDefinitionString(AbstractBeanFactory.java:1448)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1088)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:835)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741)
    ... 78 common frames omitted
Caused by: org.springframework.expression.spel.SpelEvaluationException: EL1008E: Property or field 'ticket' cannot be found on object of type 'org.springframework.beans.factory.config.BeanExpressionContext' - maybe not public?
    at org.springframework.expression.spel.ast.PropertyOrFieldReference.readProperty(PropertyOrFieldReference.java:226)
    at org.springframework.expression.spel.ast.PropertyOrFieldReference.getValueInternal(PropertyOrFieldReference.java:94)
    at org.springframework.expression.spel.ast.PropertyOrFieldReference.getValueInternal(PropertyOrFieldReference.java:81)
    at org.springframework.expression.spel.ast.CompoundExpression.getValueRef(CompoundExpression.java:51)
    at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:87)
    at org.springframework.expression.spel.ast.SpelNodeImpl.getValue(SpelNodeImpl.java:120)
    at org.springframework.expression.spel.ast.InlineList.getValueInternal(InlineList.java:95)
    at org.springframework.expression.spel.ast.SpelNodeImpl.getTypedValue(SpelNodeImpl.java:131)
    at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:297)
    at org.springframework.expression.common.CompositeStringExpression.getValue(CompositeStringExpression.java:105)
    at org.springframework.expression.common.CompositeStringExpression.getValue(CompositeStringExpression.java:42)
    at org.springframework.context.expression.StandardBeanExpressionResolver.evaluate(StandardBeanExpressionResolver.java:161)
    ... 83 common frames omitted

a解决方案是使用#{'#'}，最终结果是（工作）：

zendesk.ticket.subject.prefix=#{'#'}{{ticket.id}}