ognl表达式和el表达式_ognl取值_jsel表达式和ognl(2)

<s:property value="#map[&#39;a&#39;]"/> ---------->正确，因为其支持char

${map[&#39;a&#39;]} ------------>错误， 因为&#39;a&#39;在jsp el表达式中是字符串，不能=char。

<s:property value=&#39;#map = #{"a":123, "b":234}, ""&#39;/> --->此时key是字符串

${map[&#39;a&#39;]}

补充：

在EL表达式规范2.2中，定义了：

写道

■ The value of an IntegerLiteral ranges from Long.MIN_VALUE to

Long.MAX_VALUE

■ The value of a FloatingPointLiteral ranges from Double.MIN_VALUE to

Double.MAX_VALUE

在tomcat7.0.6实现中，jasper.jar（实现了EL2.2规范）：

AstFloatingPoint表示小数，AstInteger表示整数，其定义如下：

Java代码 public final class AstInteger extends SimpleNode

{

private volatile Number number;

public AstInteger(int id)

{

super(id);

}

protected Number getInteger()

{

if (this.number == null) {

try {

this.number = new Long(this.image);

} catch (ArithmeticException e1) {

this.number = new BigInteger(this.image);

}

}

return this.number;

}

public Class<?> getType(EvaluationContext ctx)

throws ELException

{

return getInteger().getClass();

}

public Object getValue(EvaluationContext ctx)

throws ELException

{

return getInteger();

}

}

Java代码 public final class AstFloatingPoint extends SimpleNode

{

private volatile Number number;

public AstFloatingPoint(int id)

{

super(id);

}

public Number getFloatingPoint()

{

if (this.number == null) {

try {

this.number = new Double(this.image);

} catch (ArithmeticException e0) {

this.number = new BigDecimal(this.image);

}

}

return this.number;

}

public Object getValue(EvaluationContext ctx)

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