ParseBoolean (“1”) = false... ？

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最佳答案

It accepts only a string value of "true" to represent boolean true. Best what you can do is

boolean uses_votes = "1".equals(o.get("uses_votes"));

Or if the Map actually represents an "entitiy", I think a Javabean is way much better. Or if it represents configuration settings, you may want to take a look into Apache Commons Configuration.

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According to the documentation (emphasis mine):

Parses the string argument as a boolean. The boolean returned represents the value true if the string argument is not null and is equal, ignoring case, to the string "true".

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If you're trying to get C's behavior (0 == false and everything else is true), you could do this:

boolean uses_votes = Integer.parseInt(o.get("uses_votes")) != 0;

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Java is strongly typed. 0 and 1 are numbers, which is a different type than a boolean. A number will never be equal to a boolean.

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As a note ,
for those who need to have null value for things other than "true" or "false" strings , you can use the function below

public Boolean tryParseBoolean(String inputBoolean)
{
if(!inputBoolean.equals("true")&&!inputBoolean.equals("false")) return null;
return Boolean.valueOf(inputBoolean);
}

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Thomas, I think your wrapper code, or just the condition itself, is the cleanest way to do what you want to do in java, which is convert "1" to the Boolean True value. Actually, comparing to "0" and taking the inverse would match the C behavior of treating 0 as false and everything else as true.

Boolean intStringToBoolean(numericBooleanValueString) {
return !"0".equals(numericBooleanValueString);
}

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I have a small utility function to convert all possible values into Boolean.

private boolean convertToBoolean(String value) {
boolean returnValue = false;
if ("1".equalsIgnoreCase(value) || "yes".equalsIgnoreCase(value) ||
"true".equalsIgnoreCase(value) || "on".equalsIgnoreCase(value))
returnValue = true;
return returnValue;
}

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I know this is an old thread, but what about borrowing from C syntax:

(o.get('uses_votes')).equals("1") ? true : false;

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Returns true if comes 'y', '1', 'true', 'on'or whatever you add in similar way

boolean getValue(String value) {
return ("Y".equals(value.toUpperCase())
|| "1".equals(value.toUpperCase())
|| "TRUE".equals(value.toUpperCase())
|| "ON".equals(value.toUpperCase())
);
}

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How about this?

boolean uses_votes =
( "|1|yes|on|true|"
.indexOf("|"+o.get("uses_votes").toLowerCase()+"|")
> -1
);

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I had the same question and i solved it with that:

Boolean use_vote = o.get('uses_votes').equals("1") ? true : false;