Java SQL Type setProperty(Object object, String name, String value)

Description

Tries to set the property 'name' to `value` in the given object.

License

Apache License

Parameter

Parameter	Description
object	the object
name	the property name
value	the value

Exception

Parameter	Description
SQLException	if the property cannot be set. This happens if there are no setter for the given propertyin the object or if the value cannot be wrapped to the type of the setter parameter.

Declaration

public static void setProperty(Object object, String name, String value) throws SQLException

Method Source Code


//package com.java2s;
/*/*from   ww w. j av a2  s. c  om*/
 * #%L
 * Wisdom-Framework
 * %%
 * Copyright (C) 2013 - 2014 Wisdom Framework
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */

import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class Main {
    /**
     * Tries to set the property 'name' to `value` in the given object. This assignation is made using a
     * <em>setter</em> method discovered and invoked using reflection.
     * @param object the object
     * @param name the property name
     * @param value the value
     * @throws SQLException if the property cannot be set. This happens if there are no setter for the given property
     * in the object or if the value cannot be wrapped to the type of the setter parameter.
     */
    public static void setProperty(Object object, String name, String value) throws SQLException {
        Class<?> type = object.getClass();

        PropertyDescriptor[] descriptors;
        try {
            descriptors = Introspector.getBeanInfo(type).getPropertyDescriptors();
        } catch (Exception ex) {
            throw new SQLException(ex);
        }
        List<String> names = new ArrayList<>();

        for (PropertyDescriptor descriptor : descriptors) {
            if (descriptor.getWriteMethod() == null) {
                continue;
            }

            if (descriptor.getName().equals(name)) {
                Method method = descriptor.getWriteMethod();
                Class<?> paramType = method.getParameterTypes()[0];
                Object param = toBasicType(value, paramType.getName());

                try {
                    method.invoke(object, param);
                } catch (Exception ex) {
                    throw new SQLException(ex);
                }
                return;
            }

            names.add(descriptor.getName());
        }
        throw new SQLException("No such property: " + name + ", exists.  Writable properties are: " + names);
    }

    /**
     * Transforms the given value to an instance of the given type.
     * @param value the value
     * @param type the type
     * @return an instance of the type having the wrapped value
     * @throws SQLException if the conversion is not possible.
     */
    public static Object toBasicType(String value, String type) throws SQLException {

        // Early return from first "if" condition that evaluates to true

        if (value == null) {
            return null;
        }

        if (type == null || type.equals(String.class.getName())) {
            return value;
        }

        if (type.equals(Integer.class.getName()) || type.equals(int.class.getName())) {
            try {
                return Integer.valueOf(value);
            } catch (NumberFormatException e) {
                throwSQLException(e, "Integer", value);
            }
        }

        if (type.equals(Float.class.getName()) || type.equals(float.class.getName())) {
            try {
                return Float.valueOf(value);
            } catch (NumberFormatException e) {
                throwSQLException(e, "Float", value);
            }
        }

        if (type.equals(Long.class.getName()) || type.equals(long.class.getName())) {
            try {
                return Long.valueOf(value);
            } catch (NumberFormatException e) {
                throwSQLException(e, "Long", value);
            }
        }

        if (type.equals(Double.class.getName()) || type.equals(double.class.getName())) {
            try {
                return Double.valueOf(value);
            } catch (NumberFormatException e) {
                throwSQLException(e, "Double", value);
            }
        }

        if (type.equals(Character.class.getName()) || type.equals(char.class.getName())) {
            if (value.length() != 1) {
                throw new SQLException("Invalid Character value: " + value);
            }
            return value.charAt(0);
        }

        if (type.equals(Byte.class.getName()) || type.equals(byte.class.getName())) {
            try {
                return Byte.valueOf(value);
            } catch (NumberFormatException e) {
                throwSQLException(e, "Byte", value);
            }
        }

        if (type.equals(Short.class.getName()) || type.equals(short.class.getName())) {
            try {
                return Short.valueOf(value);
            } catch (NumberFormatException e) {
                throwSQLException(e, "Short", value);
            }
        }

        // Will be "false" if not in correct format...
        if (type.equals(Boolean.class.getName()) || type.equals(boolean.class.getName())) {
            return Boolean.valueOf(value);
        }

        throw new SQLException("Unrecognized property type: " + type);
    }

    /**
     * An helper method to build and throw a SQL Exception when a property cannot be set.
     * @param cause the cause
     * @param theType the type of the property
     * @param value the value of the property
     * @throws SQLException the SQL Exception
     */
    public static void throwSQLException(Exception cause, String theType, String value) throws SQLException {
        throw new SQLException("Invalid " + theType + " value: " + value, cause);
    }
}

Java SQL Type setProperty(Object object, String name, String value)

Description

License

Parameter

Exception

Declaration

Method Source Code

Related