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从SWT ComboBox获得数据
原标题:Getting Data from a SWT ComboBox
  • 时间:2012-05-09 19:32:39
  •  标签:
  • java
  • swt

I am trying to use a data key pair in a combobox that is filled from a database. To update records in the database.
I am able to fill the combobox with data from the database, however when I go to update a record with data from the combobox I receive an error stating the I have a null pointer if the select index of the combobox is blank.
I am trying to devise a way to check if the box is blank, so that if it is I don t use it for the update.
I am thoroughly stumped on this.

Here is the code I have so far to check for null values and run the update if the values is not null. The updates work by themselves but when I try getting data from a combobox where I have to cast the datatype and nothing is selected I receive the error.

public Boolean checkStrNull(String strTest) {
    if (strTest == null) {
        return false;
    } else if (strTest.isEmpty()) {
        return false;
    } else if (strTest == "") {
        return false;
    } else {
        return true;
    }
}

public Boolean checkIntNull(int intTest) {
    if (intTest == 0) {
        return false;
    } else {
        return true;
    }
}

public void updateIntAnimal(Animal a, String strField, Integer intNew)
        throws SQLException {
    if (checkIntNull(intNew)) {
        a.updateIntField(strField, intNew);
    }
}

public void updateStrAnimal(Animal a, String strField, String strNew)
        throws SQLException {
    if (checkStrNull(strNew)) {
        a.updateStrField(strField, strNew);
    }
}
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