Fix wrong otherEntityName in relationship setter

[iconben]

I ran into this bug in one of my project, generated code is:

    @JsonIgnoreProperties(value = { "student" }, allowSetters = true)
    @OneToOne(mappedBy = "student")
    private StudentForeignerInfo foreignerInfo;

    ......

    public void setForeignerInfo(StudentForeignerInfo studentForeignerInfo) {
        if (this.foreignerInfo != null) {
            this.foreignerInfo.setStudent(null);
        }
        if (foreignerInfo != null) {
            foreignerInfo.setStudent(this);
        }
        this.foreignerInfo = studentForeignerInfo;
    }

should be:

    @JsonIgnoreProperties(value = { "student" }, allowSetters = true)
    @OneToOne(mappedBy = "student")
    private StudentForeignerInfo foreignerInfo;

    ......

    public void setForeignerInfo(StudentForeignerInfo studentForeignerInfo) {
        if (this.foreignerInfo != null) {
            this.foreignerInfo.setStudent(null);
        }
        if (studentForeignerInfo != null) {         // have to fix here
            studentForeignerInfo.setStudent(this);   // and here
        }
        this.foreignerInfo = studentForeignerInfo;
    }

In default case where name of $otherEntityName equals to name of $relationshipFieldName, the setter works well.

However if name of $otherEntityName is customized, '$relationshipFieldName' will actually be explained as 'this.$relationshipFieldName' which was just set parent to null at the preceding line but again set back to 'this', this logic is apparently wrong.

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[mshima]

LGTM