java - Strange Compilation Error Involving Casting -

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i noticed rather strange when working in ide.

double x1 = 0, x2 = 0; int = (int) x1 = (int) x2;

so invalid syntax, unsurprisingly. however, it's explanation of why it's invalid syntax confuses me. when put code in eclipse luna , hover on second line, message appears says:

type mismatch: cannot convert boolean int

1 quick fix available:

change type of 'a' 'boolean'

if ignore error , proceed run anyway, throwable stack trace shows same message:

exception in thread "main" java.lang.error: unresolved compilation problems:          type mismatch: cannot convert boolean int         syntax error on token "=", <= expected

i don't understand why compiler thinks (int) x1 = (int) x2 sort of comparison evaluates true or false. have idea of why so?

the castoperator has higher priority assignment operators. due this, can't assign cast value x1, since compiler interprets as: 

... cast x1 integer assign (int) x2 value of (int) x1 ...

step 2 won't work, since (int) x1 no lvalue (sry using term c++, have no idea if there exists synonym in java).


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