Stringtemplate compare strings does not work
Can someone explain why this does not work ?
StringTemplate query = new StringTemplate("hello " +
"$if(param==\"val1\")$" +
开发者_JAVA百科 " it works! " +
"$endif$ " +
"world");
query.setAttribute("param", "val1");
System.out.println("result: "+query.toString());
It throws
eval tree parse error :0:0: unexpected end of subtree at org.antlr.stringtemplate.language.ActionEvaluator.ifCondition(ActionEvaluator.java:815) at org.antlr.stringtemplate.language.ConditionalExpr.write(ConditionalExpr.java:99)
ST doesn't allow computation in the templates. That would make it part of the model.
You can't compare strings inside stringtemplate, unfortunately, but you can send a result of such a comparison into template as a parameter:
StringTemplate query = new StringTemplate("hello " +
"$if(paramEquals)$" +
" it works! " +
"$endif$ " +
"world");
query.setAttribute("paramEquals", param.equals("val1"));
System.out.println("result: "+query.toString());
It might not be what you're looking for, since every time you need to add a comparison you have to pass an extra parameter, and for loops it's even worse. But this is one workaround that may work for simple cases.
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