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  3. javax.el.ELException

Java 类javax.el.ELException 实例源码

项目：lams    文件：ELResolverImpl.java    
public Object getValue(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null) {
        context.setPropertyResolved(true);
        if (property != null) {
            try {
                return this.variableResolver.resolveVariable(property
                        .toString());
            } catch (javax.servlet.jsp.el.ELException e) {
                throw new ELException(e.getMessage(), e.getCause());
            }
        }
    }

    if (!context.isPropertyResolved()) {
        return getDefaultResolver().getValue(context, base, property);
    }
    return null;
}
项目：apache-tomcat-7.0.73-with-comment    文件：ELSupport.java    
@SuppressWarnings("unchecked")
public static final Enum<?> coerceToEnum(final Object obj,
        @SuppressWarnings("rawtypes") Class type) {
    if (obj == null || "".equals(obj)) {
        return null;
    }
    if (type.isAssignableFrom(obj.getClass())) {
        return (Enum<?>) obj;
    }

    if (!(obj instanceof String)) {
        throw new ELException(MessageFactory.get("error.convert",
                obj, obj.getClass(), type));
    }

    Enum<?> result;
    try {
         result = Enum.valueOf(type, (String) obj);
    } catch (IllegalArgumentException iae) {
        throw new ELException(MessageFactory.get("error.convert",
                obj, obj.getClass(), type));
    }
    return result;
}
项目：lazycat    文件：AstIdentifier.java    
@Override
public boolean isReadOnly(EvaluationContext ctx) throws ELException {
    VariableMapper varMapper = ctx.getVariableMapper();
    if (varMapper != null) {
        ValueExpression expr = varMapper.resolveVariable(this.image);
        if (expr != null) {
            return expr.isReadOnly(ctx.getELContext());
        }
    }
    ctx.setPropertyResolved(false);
    boolean result = ctx.getELResolver().isReadOnly(ctx, null, this.image);
    if (!ctx.isPropertyResolved()) {
        throw new PropertyNotFoundException(MessageFactory.get("error.resolver.unhandled.null", this.image));
    }
    return result;
}
项目：tomcat7    文件：ImplicitObjectELResolver.java    
@Override
public boolean isReadOnly(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null && property != null) {
        int idx = Arrays.binarySearch(SCOPE_NAMES, property.toString());
        if (idx >= 0) {
            context.setPropertyResolved(true);
            return true;
        }
    }
    return false;
}
项目：apache-tomcat-7.0.73-with-comment    文件：AstEmpty.java    
@Override
public Object getValue(EvaluationContext ctx)
        throws ELException {
    Object obj = this.children[0].getValue(ctx);
    if (obj == null) {
        return Boolean.TRUE;
    } else if (obj instanceof String) {
        return Boolean.valueOf(((String) obj).length() == 0);
    } else if (obj instanceof Object[]) {
        return Boolean.valueOf(((Object[]) obj).length == 0);
    } else if (obj instanceof Collection<?>) {
        return Boolean.valueOf(((Collection<?>) obj).isEmpty());
    } else if (obj instanceof Map<?,?>) {
        return Boolean.valueOf(((Map<?,?>) obj).isEmpty());
    }
    return Boolean.FALSE;
}
项目：apache-tomcat-7.0.73-with-comment    文件：AstIdentifier.java    
@Override
public void setValue(EvaluationContext ctx, Object value)
        throws ELException {
    VariableMapper varMapper = ctx.getVariableMapper();
    if (varMapper != null) {
        ValueExpression expr = varMapper.resolveVariable(this.image);
        if (expr != null) {
            expr.setValue(ctx.getELContext(), value);
            return;
        }
    }
    ctx.setPropertyResolved(false);
    ctx.getELResolver().setValue(ctx, null, this.image, value);
    if (!ctx.isPropertyResolved()) {
        throw new PropertyNotFoundException(MessageFactory.get(
                "error.resolver.unhandled.null", this.image));
    }
}
项目：apache-tomcat-7.0.73-with-comment    文件：ExpressionBuilder.java    
public MethodExpression createMethodExpression(Class<?> expectedReturnType,
        Class<?>[] expectedParamTypes) throws ELException {
    Node n = this.build();
    if (!n.isParametersProvided() && expectedParamTypes == null) {
        throw new NullPointerException(MessageFactory
                .get("error.method.nullParms"));
    }
    if (n instanceof AstValue || n instanceof AstIdentifier) {
        return new MethodExpressionImpl(expression, n, this.fnMapper,
                this.varMapper, expectedReturnType, expectedParamTypes);
    } else if (n instanceof AstLiteralExpression) {
        return new MethodExpressionLiteral(expression, expectedReturnType,
                expectedParamTypes);
    } else {
        throw new ELException("Not a Valid Method Expression: "
                + expression);
    }
}
项目：tomcat7    文件：AstEmpty.java    
@Override
public Object getValue(EvaluationContext ctx)
        throws ELException {
    Object obj = this.children[0].getValue(ctx);
    if (obj == null) {
        return Boolean.TRUE;
    } else if (obj instanceof String) {
        return Boolean.valueOf(((String) obj).length() == 0);
    } else if (obj instanceof Object[]) {
        return Boolean.valueOf(((Object[]) obj).length == 0);
    } else if (obj instanceof Collection<?>) {
        return Boolean.valueOf(((Collection<?>) obj).isEmpty());
    } else if (obj instanceof Map<?,?>) {
        return Boolean.valueOf(((Map<?,?>) obj).isEmpty());
    }
    return Boolean.FALSE;
}
项目：apache-tomcat-7.0.73-with-comment    文件：ELSupport.java    
public static final Character coerceToCharacter(final Object obj)
        throws ELException {
    if (obj == null || "".equals(obj)) {
        return Character.valueOf((char) 0);
    }
    if (obj instanceof String) {
        return Character.valueOf(((String) obj).charAt(0));
    }
    if (ELArithmetic.isNumber(obj)) {
        return Character.valueOf((char) ((Number) obj).shortValue());
    }
    Class<?> objType = obj.getClass();
    if (obj instanceof Character) {
        return (Character) obj;
    }

    throw new ELException(MessageFactory.get("error.convert",
            obj, objType, Character.class));
}
项目：tomcat7    文件：TestELParser.java    
@Test
public void testJavaKeyWordIdentifier() {
    ExpressionFactory factory = ExpressionFactory.newInstance();
    ELContext context = new ELContextImpl();

    TesterBeanA beanA = new TesterBeanA();
    beanA.setInt("five");
    ValueExpression var =
        factory.createValueExpression(beanA, TesterBeanA.class);
    context.getVariableMapper().setVariable("this", var);

    // Should fail
    Exception e = null;
    try {
        factory.createValueExpression(context, "${this}", String.class);
    } catch (ELException ele) {
        e = ele;
    }
    assertNotNull(e);
}
项目：apache-tomcat-7.0.73-with-comment    文件：ExpressionBuilder.java    
/**
 *
 */
public ExpressionBuilder(String expression, ELContext ctx)
        throws ELException {
    this.expression = expression;

    FunctionMapper ctxFn = ctx.getFunctionMapper();
    VariableMapper ctxVar = ctx.getVariableMapper();

    if (ctxFn != null) {
        this.fnMapper = new FunctionMapperFactory(ctxFn);
    }
    if (ctxVar != null) {
        this.varMapper = new VariableMapperFactory(ctxVar);
    }
}
项目：lams    文件：ELResolverImpl.java    
public Class<?> getType(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null) {
        context.setPropertyResolved(true);
        if (property != null) {
            try {
                Object obj = this.variableResolver.resolveVariable(property
                        .toString());
                return (obj != null) ? obj.getClass() : null;
            } catch (javax.servlet.jsp.el.ELException e) {
                throw new ELException(e.getMessage(), e.getCause());
            }
        }
    }

    if (!context.isPropertyResolved()) {
        return getDefaultResolver().getType(context, base, property);
    }
    return null;
}
项目：lazycat    文件：ELResolverImpl.java    
@Override
public Class<?> getType(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null) {
        context.setPropertyResolved(true);
        if (property != null) {
            try {
                Object obj = this.variableResolver.resolveVariable(property.toString());
                return (obj != null) ? obj.getClass() : null;
            } catch (javax.servlet.jsp.el.ELException e) {
                throw new ELException(e.getMessage(), e.getCause());
            }
        }
    }

    if (!context.isPropertyResolved()) {
        return elResolver.getType(context, base, property);
    }
    return null;
}
项目：tomcat7    文件：ExpressionBuilder.java    
private void prepare(Node node) throws ELException {
    try {
        node.accept(this);
    } catch (Exception e) {
        if (e instanceof ELException) {
            throw (ELException) e;
        } else {
            throw (new ELException(e));
        }
    }
    if (this.fnMapper instanceof FunctionMapperFactory) {
        this.fnMapper = ((FunctionMapperFactory) this.fnMapper).create();
    }
    if (this.varMapper instanceof VariableMapperFactory) {
        this.varMapper = ((VariableMapperFactory) this.varMapper).create();
    }
}
项目：tomcat7    文件：ScopedAttributeELResolver.java    
@Override
public void setValue(ELContext context, Object base, Object property,
        Object value) throws NullPointerException,
        PropertyNotFoundException, PropertyNotWritableException,
        ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null) {
        context.setPropertyResolved(true);
        if (property != null) {
            String key = property.toString();
            PageContext page = (PageContext) context
                    .getContext(JspContext.class);
            int scope = page.getAttributesScope(key);
            if (scope != 0) {
                page.setAttribute(key, value, scope);
            } else {
                page.setAttribute(key, value);
            }
        }
    }
}
项目：tomcat7    文件：ScopedAttributeELResolver.java    
@Override
public Object getValue(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null) {
        context.setPropertyResolved(true);
        if (property != null) {
            String key = property.toString();
            PageContext page = (PageContext) context
                    .getContext(JspContext.class);
            return page.findAttribute(key);
        }
    }

    return null;
}
项目：lams    文件：AstValue.java    
public Object getValue(EvaluationContext ctx) throws ELException {
    Object base = this.children[0].getValue(ctx);
    int propCount = this.jjtGetNumChildren();
    int i = 1;
    Object property = null;
    ELResolver resolver = ctx.getELResolver();
    while (base != null && i < propCount) {
        property = this.children[i].getValue(ctx);
        if (property == null) {
            return null;
        } else {
            ctx.setPropertyResolved(false);
            base = resolver.getValue(ctx, base, property);
        }
        i++;
    }
    return base;
}
项目：lams    文件：WebApplicationContextFacesELResolver.java    
@Override
public Object getValue(ELContext elContext, Object base, Object property) throws ELException {
    if (base != null) {
        if (base instanceof WebApplicationContext) {
            WebApplicationContext wac = (WebApplicationContext) base;
            String beanName = property.toString();
            if (logger.isTraceEnabled()) {
                logger.trace("Attempting to resolve property '" + beanName + "' in root WebApplicationContext");
            }
            if (wac.containsBean(beanName)) {
                if (logger.isDebugEnabled()) {
                    logger.debug("Successfully resolved property '" + beanName + "' in root WebApplicationContext");
                }
                elContext.setPropertyResolved(true);
                try {
                    return wac.getBean(beanName);
                }
                catch (BeansException ex) {
                    throw new ELException(ex);
                }
            }
            else {
                // Mimic standard JSF/JSP behavior when base is a Map by returning null.
                return null;
            }
        }
    }
    else {
        if (WEB_APPLICATION_CONTEXT_VARIABLE_NAME.equals(property)) {
            elContext.setPropertyResolved(true);
            return getWebApplicationContext(elContext);
        }
    }

    return null;
}
项目：tomcat7    文件：JasperELResolver.java    
@Override
public Object getValue(ELContext context, Object base, Object property)
    throws NullPointerException, PropertyNotFoundException, ELException {
    context.setPropertyResolved(false);

    int start;
    Object result = null;

    if (base == null) {
        // call implicit and app resolvers
        int index = 1 /* implicit */ + appResolversSize;
        for (int i = 0; i < index; i++) {
            result = resolvers[i].getValue(context, base, property);
            if (context.isPropertyResolved()) {
                return result;
            }
        }
        // skip collection-based resolvers (map, resource, list, array, and
        // bean)
        start = index + 5;
    } else {
        // skip implicit resolver only
        start = 1;
    }

    for (int i = start; i < size; i++) {
        result = resolvers[i].getValue(context, base, property);
        if (context.isPropertyResolved()) {
            return result;
        }
    }

    return null;
}
项目：lams    文件：AstIdentifier.java    
public Object getValue(EvaluationContext ctx) throws ELException {
    VariableMapper varMapper = ctx.getVariableMapper();
    if (varMapper != null) {
        ValueExpression expr = varMapper.resolveVariable(this.image);
        if (expr != null) {
            return expr.getValue(ctx.getELContext());
        }
    }
    ctx.setPropertyResolved(false);
    return ctx.getELResolver().getValue(ctx, null, this.image);
}
项目：lams    文件：ELSupport.java    
/**
 * @param obj0
 * @param obj1
 * @return
 * @throws EvaluationException
 */
public final static int compare(final Object obj0, final Object obj1)
        throws ELException {
    if (obj0 == obj1 || equals(obj0, obj1)) {
        return 0;
    }
    if (isBigDecimalOp(obj0, obj1)) {
        BigDecimal bd0 = (BigDecimal) coerceToNumber(obj0, BigDecimal.class);
        BigDecimal bd1 = (BigDecimal) coerceToNumber(obj1, BigDecimal.class);
        return bd0.compareTo(bd1);
    }
    if (isDoubleOp(obj0, obj1)) {
        Double d0 = (Double) coerceToNumber(obj0, Double.class);
        Double d1 = (Double) coerceToNumber(obj1, Double.class);
        return d0.compareTo(d1);
    }
    if (isBigIntegerOp(obj0, obj1)) {
        BigInteger bi0 = (BigInteger) coerceToNumber(obj0, BigInteger.class);
        BigInteger bi1 = (BigInteger) coerceToNumber(obj1, BigInteger.class);
        return bi0.compareTo(bi1);
    }
    if (isLongOp(obj0, obj1)) {
        Long l0 = (Long) coerceToNumber(obj0, Long.class);
        Long l1 = (Long) coerceToNumber(obj1, Long.class);
        return l0.compareTo(l1);
    }
    if (obj0 instanceof String || obj1 instanceof String) {
        return coerceToString(obj0).compareTo(coerceToString(obj1));
    }
    if (obj0 instanceof Comparable) {
        return (obj1 != null) ? ((Comparable) obj0).compareTo(obj1) : 1;
    }
    if (obj1 instanceof Comparable) {
        return (obj0 != null) ? -((Comparable) obj1).compareTo(obj0) : -1;
    }
    throw new ELException(MessageFactory.get("error.compare", obj0, obj1));
}
项目：lams    文件：SpringBeanELResolver.java    
@Override
public Class<?> getType(ELContext elContext, Object base, Object property) throws ELException {
    if (base == null) {
        String beanName = property.toString();
        BeanFactory bf = getBeanFactory(elContext);
        if (bf.containsBean(beanName)) {
            elContext.setPropertyResolved(true);
            return bf.getType(beanName);
        }
    }
    return null;
}
项目：lazycat    文件：JasperELResolver.java    
@Override
public Object getValue(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    context.setPropertyResolved(false);

    int start;
    Object result = null;

    if (base == null) {
        // call implicit and app resolvers
        int index = 1 /* implicit */ + appResolversSize;
        for (int i = 0; i < index; i++) {
            result = resolvers[i].getValue(context, base, property);
            if (context.isPropertyResolved()) {
                return result;
            }
        }
        // skip collection-based resolvers (map, resource, list, array, and
        // bean)
        start = index + 5;
    } else {
        // skip implicit resolver only
        start = 1;
    }

    for (int i = start; i < size; i++) {
        result = resolvers[i].getValue(context, base, property);
        if (context.isPropertyResolved()) {
            return result;
        }
    }

    return null;
}
项目：lams    文件：AstNegative.java    
public Object getValue(EvaluationContext ctx)
        throws ELException {
    Object obj = this.children[0].getValue(ctx);

    if (obj == null) {
        return new Long(0);
    }
    if (obj instanceof BigDecimal) {
        return ((BigDecimal) obj).negate();
    }
    if (obj instanceof BigInteger) {
        return ((BigInteger) obj).negate();
    }
    if (obj instanceof String) {
        if (isStringFloat((String) obj)) {
            return new Double(-Double.parseDouble((String) obj));
        }
        return new Long(-Long.parseLong((String) obj));
    }
    if (obj instanceof Long) {
        return new Long(-((Long) obj).longValue());
    }
    if (obj instanceof Double) {
        return new Double(-((Double) obj).doubleValue());
    }
    if (obj instanceof Integer) {
        return new Integer(-((Integer) obj).intValue());
    }
    if (obj instanceof Float) {
        return new Float(-((Float) obj).floatValue());
    }
    if (obj instanceof Short) {
        return new Short((short) -((Short) obj).shortValue());
    }
    if (obj instanceof Byte) {
        return new Byte((byte) -((Byte) obj).byteValue());
    }
    Long num = (Long) coerceToNumber(obj, Long.class);
    return new Long(-num.longValue());
}
项目：apache-tomcat-7.0.73-with-comment    文件：AstDotSuffix.java    
@Override
public void setImage(String image) {
    if (!Validation.isIdentifier(image)) {
        throw new ELException(MessageFactory.get("error.identifier.notjava",
                image));
    }
    this.image = image;
}
项目：tomcat7    文件：AstPlus.java    
@Override
public Object getValue(EvaluationContext ctx)
        throws ELException {
    Object obj0 = this.children[0].getValue(ctx);
    Object obj1 = this.children[1].getValue(ctx);
    return ELArithmetic.add(obj0, obj1);
}
项目：lams    文件：ELSupport.java    
public final static void throwUnhandled(Object base, Object property)
        throws ELException {
    if (base == null) {
        throw new PropertyNotFoundException(MessageFactory.get(
                "error.resolver.unhandled.null", property));
    } else {
        throw new PropertyNotFoundException(MessageFactory.get(
                "error.resolver.unhandled", base.getClass(), property));
    }
}
项目：apache-tomcat-7.0.73-with-comment    文件：ScopedAttributeELResolver.java    
@Override
public Class<Object> getType(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null) {
        context.setPropertyResolved(true);
        return Object.class;
    }

    return null;
}
项目：apache-tomcat-7.0.73-with-comment    文件：AstMinus.java    
@Override
public Object getValue(EvaluationContext ctx)
        throws ELException {
    Object obj0 = this.children[0].getValue(ctx);
    Object obj1 = this.children[1].getValue(ctx);
    return ELArithmetic.subtract(obj0, obj1);
}
项目：apache-tomcat-7.0.73-with-comment    文件：Node.java    
/**
 * Allow node to validate itself
 * 
 * @param ef
 * @param ctx
 * @throws ELException
 */
public void validateEL(ExpressionFactory ef, ELContext ctx)
        throws ELException {
    if (this.el != null) {
        // determine exact type
        ef.createValueExpression(ctx, this.value, String.class);
    }
}
项目：apache-tomcat-7.0.73-with-comment    文件：ValueExpressionImpl.java    
@Override
public Object getValue(ELContext context) throws PropertyNotFoundException,
        ELException {
    EvaluationContext ctx = new EvaluationContext(context, this.fnMapper,
            this.varMapper);
    Object value = this.getNode().getValue(ctx);
    if (this.expectedType != null) {
        return ELSupport.coerceToType(value, this.expectedType);
    }
    return value;
}
项目：tomcat7    文件：ScopedAttributeELResolver.java    
@Override
public Class<Object> getType(ELContext context, Object base, Object property)
        throws NullPointerException, PropertyNotFoundException, ELException {
    if (context == null) {
        throw new NullPointerException();
    }

    if (base == null) {
        context.setPropertyResolved(true);
        return Object.class;
    }

    return null;
}
项目：myfaces-trinidad    文件：MethodExpressionMethodBinding.java    
public Object invoke(FacesContext facesContext, Object[] params)
{
  try
  {
    return _me.invoke(facesContext.getELContext(), params);
  }
  // Convert EL exceptions into EvaluationExceptions
  catch (ELException ee)
  {
    throw new EvaluationException(ee.getMessage(), ee.getCause());
  }
}
项目：lams    文件：AstIdentifier.java    
public boolean isReadOnly(EvaluationContext ctx) throws ELException {
    VariableMapper varMapper = ctx.getVariableMapper();
    if (varMapper != null) {
        ValueExpression expr = varMapper.resolveVariable(this.image);
        if (expr != null) {
            return expr.isReadOnly(ctx.getELContext());
        }
    }
    ctx.setPropertyResolved(false);
    return ctx.getELResolver().isReadOnly(ctx, null, this.image);
}
项目：lazycat    文件：AstGreaterThan.java    
@Override
public Object getValue(EvaluationContext ctx) throws ELException {
    Object obj0 = this.children[0].getValue(ctx);
    if (obj0 == null) {
        return Boolean.FALSE;
    }
    Object obj1 = this.children[1].getValue(ctx);
    if (obj1 == null) {
        return Boolean.FALSE;
    }
    return (compare(obj0, obj1) > 0) ? Boolean.TRUE : Boolean.FALSE;
}
项目：lazycat    文件：AstNegative.java    
@Override
public Object getValue(EvaluationContext ctx) throws ELException {
    Object obj = this.children[0].getValue(ctx);

    if (obj == null) {
        return Long.valueOf(0);
    }
    if (obj instanceof BigDecimal) {
        return ((BigDecimal) obj).negate();
    }
    if (obj instanceof BigInteger) {
        return ((BigInteger) obj).negate();
    }
    if (obj instanceof String) {
        if (isStringFloat((String) obj)) {
            return new Double(-Double.parseDouble((String) obj));
        }
        return Long.valueOf(-Long.parseLong((String) obj));
    }
    if (obj instanceof Long) {
        return Long.valueOf(-((Long) obj).longValue());
    }
    if (obj instanceof Double) {
        return new Double(-((Double) obj).doubleValue());
    }
    if (obj instanceof Integer) {
        return Integer.valueOf(-((Integer) obj).intValue());
    }
    if (obj instanceof Float) {
        return new Float(-((Float) obj).floatValue());
    }
    if (obj instanceof Short) {
        return Short.valueOf((short) -((Short) obj).shortValue());
    }
    if (obj instanceof Byte) {
        return Byte.valueOf((byte) -((Byte) obj).byteValue());
    }
    Long num = (Long) coerceToNumber(obj, Long.class);
    return Long.valueOf(-num.longValue());
}
项目：lams    文件：AstGreaterThanEqual.java    
public Object getValue(EvaluationContext ctx)
        throws ELException {
    Object obj0 = this.children[0].getValue(ctx);
    Object obj1 = this.children[1].getValue(ctx);
    if (obj0 == obj1) {
        return Boolean.TRUE;
    }
    if (obj0 == null || obj1 == null) {
        return Boolean.FALSE;
    }
    return (compare(obj0, obj1) >= 0) ? Boolean.TRUE : Boolean.FALSE;
}
项目：apache-tomcat-7.0.73-with-comment    文件：ExpressionBuilder.java    
private Node build() throws ELException {
    Node n = createNodeInternal(this.expression);
    this.prepare(n);
    if (n instanceof AstDeferredExpression
            || n instanceof AstDynamicExpression) {
        n = n.jjtGetChild(0);
    }
    return n;
}
项目：tomcat7    文件：AstChoice.java    
@Override
public Object getValue(EvaluationContext ctx)
        throws ELException {
    Object obj0 = this.children[0].getValue(ctx);
    Boolean b0 = coerceToBoolean(obj0);
    return this.children[((b0.booleanValue() ? 1 : 2))].getValue(ctx);
}
项目：apache-tomcat-7.0.73-with-comment    文件：AstValue.java    
@Override
public boolean isReadOnly(EvaluationContext ctx) throws ELException {
    Target t = getTarget(ctx);
    ctx.setPropertyResolved(false);
    boolean result =
        ctx.getELResolver().isReadOnly(ctx, t.base, t.property);
    if (!ctx.isPropertyResolved()) {
        throw new PropertyNotFoundException(MessageFactory.get(
                "error.resolver.unhandled", t.base, t.property));            
    }
    return result;
}