JPA: how do I persist a String into a database field, type MYSQL Text

Since you’re using JPA, use the Lob annotation (and optionally the Column annotation). Here is what the JPA specification says about it:

9.1.19 Lob Annotation

A Lob annotation specifies that a
persistent property or field should be
persisted as a large object to a
database-supported large object type.
Portable applications should use the
Lob annotation when mapping to a
database Lob type. The Lob annotation
may be used in conjunction with the
Basic annotation. A Lob may be
either a binary or character type. The
Lob type is inferred from the type of
the persistent field or property, and
except for string and character-based
types defaults to Blob.

So declare something like this:

@Lob 
@Column(name="CONTENT", length=512)
private String content;

References

• JPA 1.0 specification:
  • Section 9.1.19 “Lob Annotation”