Example usage for javax.servlet.jsp.el Expression evaluate

Introduction

In this page you can find the example usage for javax.servlet.jsp.el Expression evaluate.

Prototype

public abstract Object evaluate(VariableResolver vResolver) throws ELException;

Source Link

Document

Evaluates an expression that was previously prepared.

Usage

From source file:io.undertow.test.jsp.expression.ExpressionJspTestCase.java

public static void evaluate(JspWriter out, PageContext pc, String qualifiedMethodExpression,
        String unqualifiedMethodExpression, String variableExpression) throws Exception {
    assert pc != null;
    TSFunctionMapper mapper = new TSFunctionMapper();
    ExpressionEvaluator eval = pc.getExpressionEvaluator();
    VariableResolver resolver = pc.getVariableResolver();
    assert eval != null : "Unable to obtain ExpressionEvaluator";
    Expression expr = eval.parseExpression(qualifiedMethodExpression, java.lang.String.class, mapper);
    assert expr != null;
    String result = (String) expr.evaluate(resolver);
    if (result != null) {
        if (result.equals("string")) {
            Expression expr2 = eval.parseExpression(variableExpression, javax.servlet.jsp.PageContext.class,
                    null);/*from  w  w w . j a v  a  2 s . co m*/
            if (expr2 != null) {
                PageContext pageContext = (PageContext) expr2.evaluate(resolver);
                if (pageContext != pc) {
                    out.println("Test FAILED.  Resolution didn't return expected value.");
                    out.println("PageContext returned is not the same instance as expected.");
                }
                Expression expr3 = eval.parseExpression(unqualifiedMethodExpression, java.lang.String.class,
                        mapper);
                if (expr3 != null) {
                    result = (String) expr3.evaluate(resolver);
                    if (result != null) {
                        if (result.equals("string")) {
                            out.println("Test PASSED");
                        } else {
                            out.println("Test FAILED. (l3) Expression evaluation returned unexpected value.");
                            out.println("Expected 'string', received '" + result + "'");
                        }
                    } else {
                        out.println("Test FAILED.  (l3) Expression evaluation returned null.");
                    }
                } else {
                    out.println("Test FAILED. (l3) ExpressionEvaluator.parseExpression" + " returned null.");
                }
            } else {
                out.println("Test FAILED. (l2) ExpressionEvaluator returned null.");
            }
        } else {
            out.println("Test FAILED.  (l1) Expression evaluation returned unexpected result.");
            out.println("Expected 'string', Received '" + result + "'");
        }
    } else {
        out.println("Test FAILED. (l1) Expression evaluation returned null.");
    }

}

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From source file:gov.nih.nci.cabig.caaers.utils.el.EL.java

public String evaluate(String input) {
    try {/*from  w ww . j  a v  a  2s  . co m*/
        StringReader rdr = new StringReader(input);
        ELParser parser = new ELParser(rdr);
        Object result = parser.ExpressionString();

        if (result instanceof String) {
            return (String) result;
        } else if (result instanceof Expression) {
            Expression expr = (Expression) result;
            result = expr.evaluate(this.resolver);
            return result == null ? null : result.toString();
        } else if (result instanceof ExpressionString) {
            Expression expr = (Expression) result;
            result = expr.evaluate(this.resolver);
            return result == null ? null : result.toString();
        } else if (result instanceof BinaryOperatorExpression) {
            BinaryOperatorExpression expr = (BinaryOperatorExpression) result;
            result = expr.evaluate(this.resolver, this.mapper, null);
            return result.toString();
        } else if (result instanceof BooleanLiteral) {
            BooleanLiteral expr = (BooleanLiteral) result;
            result = expr.evaluate(this.resolver, this.mapper, null);
            return result.toString();
        } else {
            System.out.println("Incorrect type returned; not String, Expression or ExpressionString");
            return "";
        }
    } catch (ParseException pe) {
        throw new RuntimeException("ParseException thrown: " + pe.getMessage(), pe);
    } catch (ELException ele) {
        throw new RuntimeException("ELException thrown: " + ele.getMessage(), ele);
    }
}

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